Well guys, I got some info from the DMV...there is no possible way to avoid paying use tax/sales tax in MD. If the car comes into Baltimore and is registered there, they will impose the tax.
So...I'm shipping the M3 to California. I have spoken with the State Board of Equalization and military members can apply for an exemption from use tax by filling out some forms, getting approval, and taking them to the DMV when you register the car.
The downside is that I'll be without my car for quite a long time, but I can't stomach paying all that money to MD when they don't deserve any of it! I'll probably coordinate a covered car carrier to ship it to the east coast once it finally arrives and gets registered in CA.
Stand by for pics of whatever beater I'm going to pick up in MD for less than $1,000!
Also, thanks to Shady and mdrobc for their help!