I am going to start with a teaser post but here are my idle temps with crap TIM and no overclocking but I think there is plenty of room to go up from here
Hardware monitor AMD Athlon 64 X2 4000+
Temperature 0 24°C (74°F) [0xCF] (Core #0)
Temperature 1 11°C (52°F) [0x9D] (Core #1)