not another one
toothpaste is ok!
EDIT according to this this colgate is good
http://www.overclockers.com/forums/archive/index.php/t-14764.html
Hardwaresecrets keep updating there thermal compound charts nearly every month.
http://www.hardwaresecrets.com/article/Thermal-Compound-Roundup-June-2011/1299
Error Margin
Since both room temperature and core temperature readings have 1 oC resolution, we adopted a 2 oC error margin, meaning temperature differences below 2 oC are considered irrelevant.