The reason it's messed up comes from the usb problem, which is why plugging it in lets it boot sometimes. So, contrary to all of tech support, fixing the usb is all you need to do to get it working same as usual again. I've outlined the steps below in the way I think makes the most sense, but read all of what I wrote to understand what you're doing before you start. The links are the specific instructions for each piece written by people smarter than me. I only take credit for figuring out what I needed to do and bringing all of their minds together in one place.
First thing is to see if you can get it booted. Best bet is to take out the battery and charger, hold down the power button for 10 seconds, then connect the charger and battery and boot. If you can't do that then your only option would be to try some fastboot adb trickery (which is over my head) or flash the stock rom in hboot from http://www.droidforums.net/forum/dro...ncredible.html. Note which radio you have (listed in settings -> about phone somewhere or on top of hboot) to get the right file. If you can get it booted then move to the next step.
To fix the sd card and usb go to http://forum.xda-developers.com/showthread.php?t=695243.
Fastboot is in the tools folder of the android sdk, not platform-tools like adb. To get the drivers working go to http://www.flexjunk.com/2010/05/01/i...id-sd-drivers/
UPDATE: To clarify: fastboot is a completely separate (although closely related) piece of software from adb. If you do not have "fastboot.exe", download it from http://dottech.org/tipsntricks/21534...android-phone/ and follow the instructions there. Or, you can just download the full sdk from google which should include adb and fastboot. I recommend the second option, but my hard drive can take the hit. (thanks BonzTM)
UPDATE: If you get an error saying "The Program can't start because AdbWinApi.dll is missing from your computer" you need to copy that file from platform-tools to tools, then it should work (thanks Jester1614).
If you had to reflash and lost root download z4root from http://forum.xda-developers.com/showthread.php?t=833953 and do a temporary root to be able to run the commands to fix the usb.
Once the sd card and usb are fixed then it should reboot with or without the charger plugged in. Now your phone is stable and will work with unrevoked again and you should be good to go!
Note: This is what I experienced with my amoled incredible; in no way do I take responsibility for anything you do. If you try to blame me for bricking your phone I will enjoy a hearty laugh while salting my soup with your tears.