Have you ever run across some text set in an interesting typeface, and wondered what font was used? Gone are the days of poring through font specimen books or endless font samples on web sites. Instead, try WhatTheFont.
This free tool from Bitstream lets you upload a scan of a type sample, and then it automatically tries to identify the font from the sample you've uploaded. Depending on the quality of the sample you've scanned, it works amazingly well.
If the automatic recognition doesn't work, you can submit the image to the WhatTheFont Forum, where real live actual people will help you solve the case.
If you have an iPhone, you can just snap a photo of the font in question and use the WhatTheFont for iPhone app to quickly identify it, no scanning and web uploading required. Near instant gratification!
Fontscape helps you choose a typeface by organizing typefaces into many different categories, such as appearance, dimensions, mood, etc.