Ask HN: What do you use to record ideas/IP (lab notebook)?

I'm thinking of starting up some ventures in the biomedical space, and am wondering what most of you use to keep track of inventions, intellectual property, and other documentation? The classic answer is a hardbound lab notebook with numbered pages (ideally witnessed by a third party) but I am interested in a digital solution that is indexable/searchable. Is Git considered a viable way to do this? Evernote? All opinions appreciated.