And old question: What is faith?

This came up recently on a forum I read and am an occasional contributor. It reminded me that in spite of years of instruction I still don't really know what faith is. Now over the years I have heard many a platitudinal definition to which I would nod my head, but my inner voice was always saying: yeah, okay, I don't disagree but it sounds like word salad rather than substance, and it's not really helpful. Note: I blame myself, not my teachers. I just don't get it.

Here is something I wrote years ago (slightly modified). I'm more or less in the same position:

I don't actually know what faith is. It is not simple intellectual assent--i.e., belief. The bible speaks of some who believe but are lost. Nor is it "blind." Hebrews 11 has the faith hall of fame, and lists people who did not need blind faith for they saw and spoke to god. Abraham's faith was hardly blind, with the execption that he had faith that God's promise of redemption would be fulfilled in his future. If blind faith was the ultimate virtue, Gideon (who demanded physical proof) would stand condemned--instead he shows up in Hebrews 11 as a faith hero. Faith (πίστις), I think, is closer to trust than to believe. But it appears to be more than trust. It is not at all clear that Simon the Magician of Acts 8 (whom we know believed) lacked trust. 

The best I have heard is the way Grudem puts it, which works for me: faith is coming to God and saying: "I got nothing."