One of my favorite applications on my computer is definitely Evernote, but there are a lot of people I talk with that don’t like the complexity it has to offer. They just want something simple that they can use to jot down a phone number or other basic information. For them I typically recommend Simplenote since so many different apps have been created to sync with this free online service.
If you use Simplenote you may want to check out an equally simple desktop application called Notes that syncs with the Simplenote service.
Look like really simple, yet quick and easy ways to jot down notes.
I know I will be checking these out for personal use.
Also, I like the Dropbox idea, so I don't have to worry about copying to a thumbdrive or something to keep with me.