@MobyTurbo,

But you said you did manage to charge it (at least once?). Try removing the battery for a few minutes, then put it back on and plug the charger. If you don't see any LED activity try to move the cable a bit in case it's not connecting properly (I have 3 N900s and 3 chargers, in some combinations of N900 and charger I have that issue).

Please describe exactly what you see on the LED (blinking red/orange, solid yellow, etc.)