Open Source Tax Products?

sub7 asks: "That time of the year is upon as again: Tax Season. Those of us living in the U.S. are busy fumbling with various forms with awkward names and meaningless garble on them. Being a lazy BOFH, I went to H & R Block to see how much it would cost for them to prepare and file my taxes. They estimated -at least- $175, if not more! I knew it was cheaper to buy some software to handle my taxes. So I headed down to my local office supply conglomerate and picked up Turbo Tax 2004 Premier for $69.99. Being an OSS user for nearly 6 years I have never even considered an OSS tax solution product (probably because I ph34r t4x s34s0n!). So I turn to Slashdot to ask: Are there any projects equivalent to Turbo Tax or the other tax products out there for the OSS community?"