Gmail File Space (GSpace) is a Firefox extension that allows you to use your Gmail account for file storage. It works much like the FireFTP extension (or any FTP program for that matter): You just select the file in the left pane, create a â€œfolderâ€ in the right pane, and then click the button to transfer the selected file to the specified folder. GSpace sends you an email from yourself with the file as an attachment. Retrieval is just the opposite, or you can just download the file manually.
The way that it works is actually quite clever: GSpace adds a pipe delimited string of text as the subject line that, when parsed out, contains all the necessary data to recreate the virtual path to the file. It also sends an email for each folder you create, again, with the necessary data to recreate it later.
Gmail imposes a 10MB maximum upload size so I use WinSplit to break up large files into 10MB parts that can be reassembled later (using WinSplit, of course). Gmail also imposes a â€œNo Executablesâ€ policy but that is easily circumvented by GSpace, at least for now.