I posted this on another forum and thought it might be interesing here too.
I make raised bed gardens out of cedar decking material. It was pretty easy to make my own sinkbridge with some left overs from my work. The cedar is really good for this because it handles being wet very well. No mold or rot to speak of and it doesn't warp to any degree that would interfere with being used a sink bridge.
Measure your sink, and cut a board to size. Then cut a couple of blocks to attach for keeping the bridge in place. With the board on the sink just hold one of the blocks against one side of the sink. Then holding them together for fit just pull it away and attach the block. Then repeat for the other end. I like using a 6 inch board but a 4 inch wide one will do fine too. Use what you have around if you can I say.
Sinkbridge ready to be used.
See the blocks? Install them to fit to your sink and keep the bridge from moving on you.
Attach the blocks with a couple of screws.
I sanded the edges and corners on mine a little to make sure there are no splinters.
Not a must but a damp washcloth or disposable towel between the bridge and stone will keep it steady.
A "handywipe" type of "semi-disposable" towel really works well.