I see that the Haynes book of lies museum is in your general neighborhood... Wondering if it's worth wasting an afternoon having a walk around. I'll be goofing around for a few days after IMM. "Typical" yank not caring about wasting fuel just wandering around aimlessly.
Anything else worthwhile nearby? Bear in mind that I don't really care too much for "tourist" stuff... If admission is charged, I usually go running in the other direction. Most of it has been too "Disney-fied" for my tastes. Decent museums/collections are about my only exception. I generally try to shop, eat, etc. where the locals hang out.
If travelling down the A303 you might want to see Stonehenge -bit of a tourist trap - if late at night it is possible to park on one of the tracks nearby ad get a good view - and good atmosphere without the crowds ;D