After painting with water-based paint I usually clean my brushes (or rollers) by simply rinsing them under running hot water (as hot as my hands can take) straight from the faucet.
After thorough rinsing I shake of the water as much as possible and hang them somewhere, with the hairs down, to further leak out and dry. This has served me well for years.
Now a friend of mine is telling me I should rinse the brushes with soap and warm (but not HOT) water.
After some Googling around I find that both variants seem about equally popular.
The pros and cons given for either method range from "sounds sensible" (soap may leave a residue in the brush affecting the next paint-job) to rather bizarre (hot water dissolves the hairs of the brush).
So I like to hear your opinions. Preferably with arguments for one method or the other.