I have a bottle of Farouk's Biosilk "Silk Therapy" - one of those serums that are supposed to make your hair smooth and shiny- I noticed that in the instructions on the bottle that it can also be used on the skin. The main ingredients are cyclomethicone and dimethicone, so I tried it yesterday and put my makeup over it (I use bare minerals) and I have to admit, my makeup looked fresh all day...and this stuff SAYS it's safe for skin. It felt nice too. I think a 2 oz bottle is about $15, maybe less depending on where you buy it. Not as cheap as the monostat, but probably cheaper than alot of the foundation primers out there- plus it doubles as a hair treatment!