I can't believe I haven't seen anybody point out Excel:
I've been using the worksheet he provides to do my taxes for about 5 years now. He asks for donations. It's incredible. It is literally an implementation in Excel of the 1040 form set, and it turns out that those forms are incredibly easy to use if you just automate the stupid parts (if line x is greater than line y, subtract and enter result, otherwise enter zero) and tie the worksheets into the file. It's awesome.
It does not ask you a series of questions, it does not offer ways to help find deductions. It is simply an easy way to fill out the basic 1040 and damn near all of its schedules, and it turns out that doing that instead of answering an interview is really fast.