The most prolific pistol in the world, The Glock, can now be easily handled by lefties thanks to the MARS from Rainier Arms. This drop in magazine catch will take your right handed only release, and not just convert it to left handed friendly, but also make it fully ambidextrous.
The Magazine Advanced Release System is a drop in solution that allows full ambi control with no gunsmithing, a first for lefties that I am aware of. Not made of plastic, but 6061 aluminum with type III hard coat, this should be a durable addition to the durable Glock.
Looks like I will need to get an ambidextrous Glock now.