Nothing beats a fully customisable piece of paper.
“The PocketMod is a new way to keep yourself organized. Lets face it, PDAs are too expensive and cumbersome, and organizers are bulky and hard to carry around. Nothing beats a folded up piece of paper. That is until now. With the PocketMod, you can carry around the days notes, keep them organized in any way you wish, then easily transfer the notes to your PDA, spreadsheet, or planner.”
Link: PocketMod: The Free Disposable Personal Organizer (pocketmod.com)