I got my hands on a 16GB Transcend SDHC card. Wasn't cheap, but it works, and I reckon 2 of them on my N800 will beat an iPod Touch any day if it wasn't for the bad battery life.

I had a full charge before I boarded a 7-hour long flight and after watching 1 episode of a Japanese anime of 30 minutes, the 'battery low' warning came up. How disappointing!