http://www.superliminal.com/upsidedown/NQAS.htm
-- Sample: '''auo s!y+ punoJ +snf I ´beq aycnop noÁ

http://www.revfad.com/flip.html
-- Sample: .ǝuo sıɥʇ punoɟ ʇsnظ ı 'bɐq ǝɥɔnop noʎ

Yoshi wins.