DC101 will certainly come in for you. And 98 Rock should be listenable, at least in the car. I listen to it all over NoVa in the car. I don't think you'll hear 3WV too often, w/ the 11,000 watt WLTF at 1,000 feet just 40 miles from you. But looking out THAT way, 105.5 The Bone is an option, however some a-hole put up a relay of 88.5's HD-2 bluegrass on that freq. somewhere in the vicinity of Great Falls (Great Falls is on the river just outside the beltway). Its not pumping many watts but it will definitly affect signal the closer you get to dc. The Fox 99 fm is another option, albiet samwhiched right in-between Hot 99.5 & the new/future all news WNEW(but WNEWs tower is on the opposite side of the dc metro from you). The 96.9 classic rock station at "King's Dominion" is out of the question, their signal gets obliterated as soon as you pass Fredricksburg by 97.1, not to mention the fact theres a country station on that freq just on the other side of the ridge from you in Strasburg. Gainsville is kinda out there, western edge of the dc metro I'd say, a good hour to hour&half commute to dc during rush hour (40 mins non rush hour). Your going to love to hate rush hour, an G'ville is just a traffic mess. You've got a Super Target though!!! and cheap gas!! ($3.18 last weekend when i was there).
WMDM is out of the question, they are on the other side of the dc metro from you.
100.7 The Bay, classic rock station can be an option, but it'll depend on where you are at the moment you listen......meaning if you move 2 feet, you'll get Q101 (CHR) Harrisonburg, move 2 more feet, you'll get "The Bay". Those 2 stations will be fighting with each other out there.
Good luck