Janitor is my laptop; I've used it for I think more than two years; even though you might consider it "old", I'm quite comfortable with it.
Janitor is a Dell Inspiron 1300 with 2 GB of memory; even though it hasn't a top performing processor, its wide screen makes it very handy for my developing activites.
As I already told, in the recent past I had some troubles, caused by the internal fan which cheased working all of sudden.
After a lot of work, I finally made the thing I should have done in the first place: call the Dell assistance; they provided me with the obvious suggestion (i.e. to try cleaning the fan with compressed air) and it worked very well.
In the mean time, however, I tried everything else. So, I found a number of optimizations for the Inspiron and for the graphic card (which was the one showing most problems when the fan was not working).
In the end, I configured the device section of my /etc/X11/xorg.conf as follows:
Identifier "Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller"
Option "DRI" "true"
Option "AccelMethod" "exa"
Option "MigrationHeuristic" "greedy"
Option "ExaNoComposite" "false"
and I added the INTEL_BATCH="1" setting to /etc/environment.
After a reboot, I'd been able to notice a great improvement in the perfomance of my computer. Gmail is lightning fast, and everything seems a lot faster. My unittest, which last time required something like 600 seconds to be run, now ask me just for 260 seconds. That's an improvement, indeed :-)