good comment. i think my school is pulling those shennanigans. word is that the testing market is dominated by some sort of propreitary software, the developer of which can't figure out how to lock down a mac machine (USB, WiFi, optical drive, FireWire etc) to prevent cheating.
if only windows machines could be so secure in general use...who knew. this is why windows emulation on the mac isn't good enough; its a hardware hang up with the testing developers, not a software issue.
anyway, the prohibitive nature of the every-day windows experience (and the costs associated with any laptop purchase) will likely grant you some wiggle room with the school, whereby you might be able to lease a machine from the IS department on test days (as long as you've got your own machine for everything else). it may seem like a hassle, but its a small concern in the face of these endless windows vulnerabilies. why should you have to pay because the law school doesn't want to use pen and paper any more? you want to be able to use this machine in the real world, too...without losing your passwords and financial data to the russian mafia.
when the dept. of homeland security recommends that we avoid internet explorer on windows, you know its time to switch...