Guitar strings...

I was reading a blog thread about guitar string brands, and noted several comments from players whose "body chemistry" caused their strings to go dead quickly.  Or so they said.  My Classical teacher taught me to always wash my hands with soap and water before touching the guitar, to remove finger oils.  The oil gets into the windings of the bass strings and attracts and holds dirt particles, tiny bits of dead skin, etc., which can deaden a string literally overnight.  Finger oil and dirt also coat the mono-filament strings (the treble strings), which deadens them as well, though not as quickly.  Some people have oilier skin than others.  If you have oily hands, try washing them with soap, or even detergent, particularly the finger ends, right before playing.  Unless you LIKE restringing your guitar, of course!  Anybody have any other ideas on how to make strings last longer?