Peephole? Or 35mm Adapter?
 

I've been aware of some of the higher-end DOF adapters for a while now, but I'm new to the DIY approach you guys have pioneered here. (Kudos, BTW!) Lurking on the forums for the past couple of days and taking in so much info on close-up kits, achromats and ground glasses brought to mind something interesting I once saw in a bank. These large peepholes seem to have very low light loss:

http://www.doorscopes.com

I can't speak to actual light loss or optical quality, as I haven't bought one yet, but the large rear element seems to combine a 2" diameter achromat and a GG in one element. Do you think you could slap one of those critters in a tube, shake it around and get a decent adapter?

for the vibration you would want to only vibrate the ground glass.. these things seem pretty cool.. but i dont know how youd get the screen to vibrate.

More interesting info on the Door Scopes
 

I found this discussion about the optics of the Door Scope and it's ability to produce an upright (but horizontally flopped) image. It uses something called a "dove prism."

Check it out here:

http://www.opticsnotes.com/sciopticsfaq/mirror.htm

Search "dove prism" on this forum... also, "roof prism" and "roof pentaprism".

Yeah, I've been reading up on those, Jim. (Sorry for the slow uptake.) Does the roof pentprism seem to be the preferred method for everyone here? Or the magnet trick on the LCD?