How to prepare usb keys for use in linux
Most usb storage devices are formated as FAT32 when you purchase them, which can be used in modern Windows/Mac/Linux machines. If you need to format or repartition the devices and you want them to be accessable to both windows and linux a useful way is to make sure they are partioned in the FAT32 format.
Partioning
If you want to use the device also in Mac and Windows machines it should have a FAT32 partition. The manual page of the linux partioning program fdisk recomends to use the windows version of fdisk. However after some fiddling with the linux version it seemed to work (no details but it took two attempts to make it work).
Formatting
Format using windows as FAT32 - if you format as FAT this will result in errors in Linux because of the partition size limitations of FAT which windows seems to ignore.
Update
On linux GParted is a nice graphical interface for changing partitions, takes care only to select correct device, don't use these tools on your live multiuser non-backed up machine. ;ppppp