Possible source for protein/other supplements - opinions?

Hello all,

I came across this site sometime ago - www.proteinfactory.com - they have a neet-looking feature, "Protein Lab" where you can make your own supplement - pricewise, seems better than the whey powder I pick up at the grocery store. Any tips on a decent post-run supplement using this tool? Lots of options - protein type, carbs, sweeteners, supplements - I'm a bit out of my element here.

Thanks,

Mike