Files, files, where are your files? If you move around from office to office, the best place to keep them could be with an online storage or back-up service.

There are two approaches: store and share your files online, or back up all your computer data. Folder-replicating services synchronize the online folder with local clients running the proper software.

One reader runs a service based on Novell's iFolder utility. Novell’s gotten good reviews for this service, even by me in the past. Recently it extended the server options beyond NetWare to Linux and Windows 2000. Unfortunately for all Novell’s talk about Linux desktops, there’s still no Linux client for iFolder. But Windows clients can use the service, through a company server or a service, and it will keep the files synchronized between the server and all clients configured to use that particular server folder.

When you configure your primary data storage folder as the iFolder contact point, you essentially have a backup of all your data. Products from SwapDrive ($15 monthly for 250M bytes) and FolderShare ($5.90 monthly per user for unlimited storage) work similarly. Check out others through directories such as Yahoo.com and the Open Directory Project.

If sharing files among multiple people is important, you want to verify you can have private and shared folders. You'll have to create user names with access rights for each user, but that lets you keep private files private, yet share files you want. Folder-sharing services tend to make these type of arrangements easier than the back-up service vendors do, but check to verify. FolderShare offers good support for sharing a set of folders among multiple users.

SwapDrive offers some interesting options. WhaleMail bypasses the attachment-size limitations on some e-mail servers by holding the files on its system and sending notice to the intended recipient. The file destination target user then chooses when to download the file to his hard disk rather than through an e-mail download. Compression, security and notifications are part of the service. If you're ever cursed someone who sent a 9.87M-byte PowerPoint presentation as you wait for your laptop on a hotel dial-up connection, you know WhaleMail could come in handy. Get the notice, breathe a sigh of relief, and download the file when you get back home to your broadband connection.