Integrale owners (who tend to overtake a lot) stick an angled mirror in the offside corner of the windscreen to help them see down the road a bit better.
A couple of other alternatives:
(Technical) Put a mini camera in the offside wing mirror and feed it to a fold out DVD screen
(Basic) Put your other half in the passenger seat. Start to pull out - if they scream it's probably best to pull back in pronto
I'm sure someone on here posted a link to relatively self contained (just the screen and the camera and the 12v plug) system on eBay a while back. Tiny wee camera with a fish-eye lens.
It was originally supposed to be a reversing camera but someone was using it at the front on their Yank motor (possibly a Gen 3 Camaro or Firebird?).