Until recently I did not know that this was possible, but people are hacking the venerable Logitech C920 and C930e webcams. The hardware hacks allow them to be used with a diverse range of high-quality, low-cost, CS lenses.
What started as a series of hacks by Saulius Lukse in Vilnius, Lithuania has turned into a small enterprise. At his Kurokesu site he now sells various things related to his adventures in optics. That includes machined metal cases to refit the internals of the C920/C930e.