Are you having issues sometimes where the HTC Vive thinks your floor is higher or lower than it should be? Well, someone's got a fix for you.
You can download the program from here. As you can see in the video, you just place one controller on the ground, run the program, click the button with the other controller and boom. The floor's height should sort itself out.
Pretty cool, but this should be in the SteamVR settings somewhere. Until the software gets updated with this option, or if ever, there's this nice little program to do the job for you.