A tax accountant reader takes time out to write:
AMT = Alternative Minimum Tax. It is huge this year, nailing many, many folks on their 2005 tax return. The little bit of relief was allowed in 2003 & 2004 sunsetted in 2005. It will really be hitting Blue Staters (without going into excruciating detail, basically it is due to higher income and higher taxes) hard. Of course, personal exemptions are preference items and can cause AMT to hit large families. This is a political issue that is going to have to be addressed soon.
Personally, the AMT definitely hasn't affected me. That reminds me of my financial self-help book that will be coming out in time for the 2007 tax season: The New Surefire Sailer Strategy for Paying Less in Taxes: Have a Low Income!