gStorage is a file management tool, which can be used to manager your local files in a mobile phone and network files in a remote storage space. Currently, it supports those files(attachments) in your Gmail box. As we all know, the storage capacity of one free Gmail box is considerably large, up to 7Gb for the moment, and can be upgraded to 400Gb. So, with this tool, you will get a large enough disk for your phone right now. It easily converts your Gmail box to a local mapped drive and you can exchange data with your Gmail box. Another way to extend the capacity for your phone is applying for another free Gmail box, but this requires you maintaining additional accounts.
At a default installation, this software is a freeware with a little limitation -- the total size of files to be sent or downloaded should be not more than 500Kb.
Free Download: gStorage_S60_3_0_v_1_1.sisx