I'm going to post what I myself consider to be a budget build for today, now that I've looked over prices. This is different from what most people actually want normally, because I prefer to build a good base to start and upgrade later.
X3 720 Once overclocked this CPU is adequate and a great price.
Sunbeam CPU cooler Great cooler for AMD boards and comes with good paste.
Asus M4A78T-E 790GX AM3 MB $20 off with CPU combo makes this the best crossfire choice.
G.skill DDR3 1333 CAS 7
Antec 300
HIS 4850
OCZ modular 700W Enough for another 4850 and anything else you want to add.
WD 320GB HD
HP retail DVD burner
This system is ready to be upgraded to any future AM3 CPU, a second 4850, or any large single video card
X3 720 Once overclocked this CPU is adequate and a great price.
Sunbeam CPU cooler Great cooler for AMD boards and comes with good paste.
Asus M4A78T-E 790GX AM3 MB $20 off with CPU combo makes this the best crossfire choice.
G.skill DDR3 1333 CAS 7
Antec 300
HIS 4850
OCZ modular 700W Enough for another 4850 and anything else you want to add.
WD 320GB HD
HP retail DVD burner
This system is ready to be upgraded to any future AM3 CPU, a second 4850, or any large single video card