I did my taxes in California last year by way of filling out a PDF online, and doing the calculations manually. Which really bugged me - I'm not sure if there's a way to embed simple math into a PDF, but there should be if it will be used like that.
That gets me to thinking - we don't really have that much choice on our tax returns, basically 2 people would write the same return if they had the same w-4s, right?
So let's have a system where a tax return program synthesizes files - perhaps transparently. The user can make choices when need be, but instead of my employer sending me paper, how about they send me a file, digitally signed (and probably encrypted in transit to me). I then use a program to merge all of these files and it does my tax return. Kind of like Turbo-Tax, but with additional integration with these tax-files. This saves me time from reading directions, and it saves the IRS time from people making mistakes. It could even present what appears to be a 1040 to people, so they can understand why they get a refund or owe more.