Since I've been out of comms for a bit, I am going to fire-hose you guys with various stuff I have found on the web that tickles my tactical beard (I don't have one, but you get the point)
Frogpro.it has a lasercut PC. Pretty slick looking, don't know how applicable it is though.
Dueck Defense has a "backup sight base" system that takes over your Glock's rear sight channel. No messing with hardware or milling, slap this guy in, put an RMR in and adjust the RDS to work with the iron sights. Sight radius sucks, but its a tiny package.
One perspective on how gun-point interactions occur with criminals. I did search on youtube for gun robbery and most, if not all (once you disregard the BS videos) are all inside of 3 feet, at least on the first two or three pages.
Bobro is going to releasing their MRO mount soon, thankfully, that looks like a prototype they are working on.
Arisaka Defense has some sweet adjustable angle mounts out that you can use to put various things on your rail.
Trijicon MRO overview from MAC.