Typical mechanical keyboard switches are inherently a certain height, and that presents some problems for some scenarios. Even if you aren't creating a wacky design, keyboards with Cherry MX-like switches still have to be a certain thickness. If you'd like a slimmer mechanical keyboard, you should be pleased to hear about Kailh's new Mini Choc switches, model number PG1232.
The new mechanical keyswitches have a total travel of just 2.4 mm (compared to 4 mm on the Cherry MX design), and actuate in just 1.2mm. The Kailh switches require 50 gram-force to actuate, making them similar to MX Blue switches in necessary weight. The current PG1232 switches are available in clicky form only, although Kailh says that if there's interest, it will produce tactile or linear versions of the switches.
Unlike most of Kailh's offerings, the new PG1232 slim keyswitches don't have Cherry MX-compatible (cross-shaped) stems. That means you can't simply slap your favorite set of novelty keycaps on them. We're looking forward to see what kind of low-profile designs the usual keyboard suspects can create with these switches.