Which languages or dialects look nastiest when written down?

Brennus - you say that the orthography of Polish doesn't accurately reflect how it is pronounced. Are you sure? Polish sound-spelling correspondences are pretty spot-on as far as I'm concerned. Maybe there is the odd discrepancy with the "e" with a tail (sorry I can't write it down here, you know the letter I mean) but generally what you read is what you get.