What should my next upgrade be?

I've just upgraded my gaming rig a lot, added new graphic card, installed more ram and even got a new CPU. My birthday is coming up pretty soon and im having a hard time deciding what I should get as a present for my pc to upgrade it a little further. here are my specs:

Intel Core 2 Quad Q9650 3.0ghz
Sapphire ATI Radeon HD 4870 x2
Razer Barracuda AC-1 Sound card (with the razer headset)
4 gig Ram
P5N-E SLI motherboard

Now my choices are either a new monitor (now im sporting a 20" widescreen), a new motherboard or another 4870 x2 for crossfire (which i might have to get a new motherboard anyway for it to work).

plz help me decide :) Thanks!

Don't get another 4870x2, the scaling is pretty poor.

I suggest either a 24"+ monitor OR the Logitech Z-5500!

An Enginering sample (ES) of a core7 and a prototype X58, anything else is a waste..

Perhaps a pair solidstate to run in raid. :roll:

But if i were you i would just stay put and buy games to go with the rig.