The diminutive Nikon 50mm Digiscoping package is worth mentioning here. This is, after all, a digiscoping blog, too. It's a small aperture scope, but a pretty slick portable digiscoping rig. For those wanting to take the tedious guesswork out of selecting digiscoping gear, this setup is almost complete – the only thing left to select is the tripod.
This Nikon kit includes:
Nikon 50mm Fieldscope ED Straight Spotting Scope
Nikon 16x Digiscoping Eyepiece
Nikon Coolpix P4 Digital Camera
Nikon FSB-4 Digiscoping Bracket
Link: Full product description from Eagle Optics
Addendum - 12/14/2007:
I had just a few minutes at work this morning to take the Nikon kit outside to digiscope an American Tree Sparrow beneath our feeders:
The kit is very easy to use and if I had more time I could probably do very well with it. I'll try to get better results at some point in the future.