Some people may find that even with an 2GB SD card things don't quite fit (when using Win32DiskImager.exe for example to put the image on the card). We're not quite sure why - some 2GB cards just seem to be just slightly under 2GB!
You can put the image on a 4GB card no problem, then use some partition program to define the unused space at the end as, for example, a data or swap partition. Pretty easy with the disk utility program in Ubuntu (palimpsest?)
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I own the world’s worst thesaurus. Not only is it awful, it’s awful."