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This is a brief placeholder for further investigations. Metaverses are a interesting potential technology toward seamless virtual collaboration. On this topic the Crouqet Project has developed an open source prototype system, called OpenCroquet. Of the features and uses presented, I find the capability of annotating artifacts really appeling to the collaborative creation of knowledge. Here it is the annotation architecture and a brief demonstration. A nice experiment has been made where students explore a number of worlds (portals) and then collaboratively create an idea map in Croquet space about how Croquet might be used as a learning environment.

Every now and then I find pleasant tasting this small bites of wisdom; those I appreciate most are brief, puzzling and enlightening. I find it an handy way to keep always with me the lessons I valued most, my believes, or simply my “humanitas”. A stoic would have said “Omnia mea mecum porto” (I carry with me all my belongings).

Every now and then I would be pleased to share some.

The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

George Bernard Shaw

What else to add? I think nothing. Go to the Google Research Blog and check out the first post. They are really different, no doubt about it, but some introductive Powerpoint slides (We_are_different.ppt) would have been nice .

Dr Fun posted a strip about the relation between laziness, comfort and freedom which Simon Phipps briefly describes as “The greatest enemy of freedom is a happy slave”.

Once you stopped laughing, I suggest you an interesting exercise: start thinking about a better a reason to give away freedom than comfort and coolness. I really do believe it’s an hard exercise; because freedom is not the easy way, it has choices, many, and decisions, some easy some others difficult, so it avoids laziness as hell.

Think about computers and software, when the price of having freedom for your data over the coolness and the comfort of the environments where this data are stored and processed what you would choose, or better, what you have choosen?
Freedom can be attained only by the everyday practice of a lifetime; it is not be purchased at a lesser price. Sometimes this practice is simple, sometimes not.

(The final sentece is a reference to Samuale Johnson’s quote “Excellence in any department can be attained only by the labor of a lifetime; it is not to be purchased at a lesser price.”, read in Peter Norvig’s “Teach Yourself Programming in Ten Years“; this is a highly recommend reading for every aspiring software engineer/computer scientist).

If the reader has a cooler and more comfortable solution he is welcome to enlighten the (lazy) writer.

From the home page…

FreeOSZoo provides ready-to-run images of QEMU virtual computers, pre-installed with a Free Operating System and a set of popular free software. To get started, you only need to install QEMU and download a single file from the FreeOSZoo project.

FreeOSZoo is targeted at end-users, who run proprietary Operating Systems because they are not aware of the existence of Free Operating Systems like GNU/Linux, FreeBSD and other free alternatives. For this audience, FreeOSZoo is the perfect tool for testing an Operating System without modifying their computer.

Here is the page collecting the qemu images.

Virtualization is a quite powerful and useful abstraction: the availability of self-contained ready-to-roll system image really lowers the barrier to test, study, hack, develop operating systems. Assuming you are using a quite powerful machine (e.g. a 2.0 GHz P4 with 512 MB RAM Memory is suggested to have a smooth run) testing a complete software stack (operating system, database, web server, programming environment) is a push-botton experience or, in other words, it is one click away from you. It is also a huge step forward in the repeatability of software experiments, and hence in the scientific accurancy of software development; “provare et reprovare” in Galileo’s words.

This is also a nice chance to take a look at some forward-looking experiments in operating systems design as Plan9, a complete rethought of Unix concepts in a network oriented environment by the Lab who gave us Unix. The Plan9-updated image doesn’t work, or rather I didn’t find a 30-second way of getting into rio, the Plan9 window manager, however you’ll be able to download Plan9 image from the official site and boot it as a live cd to step into a quick view of the OS.

I experienced another small enlightenment, linux administration related, when I discovered bash completition. This feature proves itself useful when you use quite often the shell: during system adminstration, software compilation/testing/deployment/whatever. To enable it, edit your ~/.bashrc file (where ~ means your home directory, e.g. /home/mfabbri), with your favorite editor and uncomment the lines following the one which states # enable programmable completion features .

More extensively from a shell (or a terminal window, as gnome-terminal):

$ vi /etc/bash.bashrc

find the lines :

# enable programmable completion features (you don't need to enable
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile
# sources /etc/bash.bashrc).
#if [ -f /etc/bash_completion ]; then
# . /etc/bash_completion
#fi

and change them into

# enable programmable completion features (you don't need to enable
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile
# sources /etc/bash.bashrc).
if [ -f /etc/bash_completion ]; then
. /etc/bash_completion
fi

Logoff and login from your shell (if you are using a terminal, as gnome-terminal, restart it) , and you should be able to use completition not only for command/file names/program names, but also for program commands, for example digiting apt-get and pressing the [TAB] key should produce on the output a list of available actions as:

autoclean clean install update
build-dep dist-upgrade remove upgrade
check dselect-upgrade source

It works for many other programs, as cvs, subversion, darcs, ant, maven, java et cetera.
Java needs a special mention, use this feature with care, cause it scans the whole classpath searching for classes, so when it is dealing with huge classpaths it could slow down things a little.

As you may have noticed, you could also enable this feature system wide editing the same way the file /etc/bash.bashrc.

After man-months of hard fight between me and email clients, I discovered (through the kind contribution of a jini-users mailing list member) that long urls, that usually get wrapped by email clients, can survive without being wrapped if you put angular braces <> around them.

Simply Beautiful.

The return is limited to a MasterCard commercial … however it’s priceless!

For those who dare… I suggest downloading the MIDI version of the MacGyver Theme and using it as the default melody of your mobile .

This video takes the remixing of music one step further… into “reality” (via creating passionate users), it’s really fun and quite puzzling!