Everyone has mentioned the obvious and not so obvious reasons...for wanting or having an n900...
it's challenges and benefits...especially nowadays...

yes it is one of the few phones that are a computer ...in essence..as well...
and that runs linux...
with a physik keyboard and resistive screen...
and all the other jazz everyone has been saying...
and that yes you can work on your own programs for it..

sure there are other phones that run linux...
are they better?
some may be newer...some older...but better? ...I don't think so...

some still use the n900 as a daily...some don't...
hell ...there are some of us who still use the n770, n800 and n810 daily..


important is...
there is all the software for the devices here...and...there is the community here...and all those who help...