The lowest seed to reach the Elite 8 was #12 Missouri in 2002.
George Mason was the 11th seed in 2006 and made it all the way to the Final Four. I don't know if that's the lowest seeded team to make it to the Elite Eight or Final Four though.http://a.espncdn.com/ncaatourney/brackets/2006Bracket.pdf
No. The lowest seed to reach the Elite 8 was #12 Missouri in 2002.
In 2006, George Mason made it as a #11 seed. This is not necessarily the lowest seed of all time to make it to the final four.
Prior to reaching the Elite Eight in 2008, Xavier had been there just once before. That was in 2004 when, as a 7 seed, they lost to Duke in the Atlanta Regional final 66-63.
Villanova as a #8 seed in 1985 and won the championship game that year
There has been two number eight seeds (the lowest seeds) to make it to the title game: * UCLA in 1980 and *Villanova in 1985 Villanova won the national championship that year
8 seed UCLA lost the championship game in 1980, but 8 seed Villanova beat Georgetown in 1985.