rclymer:
Im not too sure what I used, Ill try that one out. Thanks, you had no problems putting it to sleep with the avr/sleep library?
I've only slept an ATmega328. This evening if I get a chance (and if you had no luck with the Core I linked to) I will try to sleep my ATtiny84 and wake it from an interrupt.
EDIT:
Why are you attaching a RISING interrupt? Don't you want to use the internal pullup and wake on FALLING?