If you didn't know, HTC has promised to provide bootloader unlock support for all devices released after September of 2011 as well as many others released before, and they have been keeping good on that promise with added support for many devices over the last few months.
They're still going strong, and added several more devices to the list earlier today.
There you have it, the newly supported devices are the HTC Desire Z, ChaCha, Aria, Droid Incredible, Status, and T-Mobile G2. If you own one listed above, you can head on over to the HTCDev website to unlock your bootloader now.
As always, you're warned of the potential harm you can do to your device with an unlocked bootloader, and it is strongly recommended that only experienced users proceed.