Arkaign
Lifer
Perhaps the OP can get a 2nd-hand i5 or i7 in the classifieds? Maybe even a Nehalam-based chip. There's an i7 920 combo with motherboard + RAM going for $250 in classifieds right now, which is about what you'd expect to spend in just an i3 or FX + board, and it's without a doubt much faster.
Used is nearly always the best value! I like this idea!