If you have an old web cam laying around, you can turn it into a functional spy cam with only a bit of hardware handiwork.
At Ugolog, a company specialising in simple video monitoring using web cams, they have a tutorial on how to hide a web cam inside an old power transformer. The tutorial requires no tools beyond the basic toolbox staples, like a drill and pliers. The end result is surprisingly polished, and the technique could easily be adapted to help you hide a camera in nearly anything. The best objects for hiding the web cam, of course, are objects that already have a cord attached—a stuffed unicorn with a black cord trailing out, we'd guess, is more suspicious to a nervous thief or interloper than an alarm clock. For more pictures and a step by step guide, check out the link below. Thanks Alexander!