Haha, yes my friends give me some ideas, but I never use them since they don't really realise what an adventure game is, and they come up with Shoot'em up ideas. My friend says my game needs 'killing people' coz into violent games
One of the things that helps me a lot is making a word file and splitting into sections-characters, plotline, gameplay, features etc. Then when i get an idea i write it down there. It helps to like figure it all out and have stuff to check back on than have it all in your head.