There are many "Rube Goldberg" fans out there and are building their own release cables.

I have not see one that can be called "universal".

They are pretty much custom made for each model camera.

The easiest to make is an aluminum bracket that attaches to the tripod mount with a screw. You can get the aluminum bars at Home Depot.

A few examples here:

http://www.steves-digicams.com/nikon_cable.html

To see all types.....go here:

http://www.google.com/search?hl=en&lr=&q=%22cable+release%22+%22digital+camera%22&btnG=Search

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