Ubuntu should maintain a database of programs for different file types, so that instead of clicking a file and discovering there is no supported program installed.. Instead, they should be prompted with something like the following:

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- There are no known programs installed to open "jakebox" files.
- Ubuntu can install one of the following programs from APT automatically. We believe they may be able to open the file: (Show packages: eg. KJakebox, JB)
- Or you may select an existing program to attempt to open it with. (Show existing program list)
- Or just cancel
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This would be integrated with synaptic and catch all unsupported file types, and means that even advanced users wont have issues opening files they have never seen before.

I think all hands would be up on brainstorm when i asked if people have at least once been sent something they had to google to work out how to open.