We need a super cheap microscope for electronics use

[DavidDLC]

Maybe can be based on this ?

http://news.yahoo.com/blogs/this-could-be-big-abc-news/super-cheap-paper-microscope-could-save-millions-lives-133616732.html?vp=1

[Tinkerer]

Very interesting. That I think could very well be the end all of cheap portable microscope for the field for quick diagnostics.

As for something that could be a bit more precise and only a little more expensive, I would have to go with a device based off of this: http://www.ted.com/talks/josh_silver_demos_adjustable_liquid_filled_eyeglasses
Instead of having a fixed solid lense, you adjust a liquid filled 'bag' to change the focus.