No problem, I've been meaning to do it for a while now, but its always difficult to get my butt out in the cold and wait for disk benchmark to finish.
I'm starting to run out of memory on the 32gb version, and i'm also considering the 60gb version. I did pay nearly 200 for the 30gb version, spending another 200 is starting to hurt my pocket.
It sounds like a CF may be your only option.
I purchased a 30gb OCZ vertex. I picked it up for 109$CND from ncix.com, including a mail in rebate that I am to lazy to mail in.
As far as sub-$100 goes... Depending on how much and the quality of your recording and your PCs computational power goes to compress that data, it seems like you're gonna want a good deal of space for video recording. If it were me, I would stick with a rotational 5400rpm disk (160gb~320gb scorpio blues are good) and have it hookup to a e-sata or usb in a way that would allow it to be fairly modular. On really cold nights, just bring it in. There should be any problem with it operating in cold temperatures as long as you do leave it sitting out in the cold long enough for the fluid to freeze in it. While operating, the drive should be able to generate enough heat to prevent it from freezing. Downside is of course, you'll have to remember to bring it in with you whenever it gets too cold.
Now if you do have fairly decent processing power and can encode your videos as they are written to disk, and don't need much space to store them on, I'd go with a 32gb CF card, which will put you in the ~$100 ballpark.
Here in Turkey you can see nearly all climates!
With my carpc, the first summer trip I made was to Ayvalık then Mersin.
In Ayvalık I saw 41C, in Mersin I saw 48C. My hdd was ragular 3.5 7200rpm 80gb hdd. Nothing happened. With that hdd the lowest I saw was -12C I think. Carpc could not bootup until hdd got worm. But after, worked flawlessly.
With my new carpc, I went to Bodrum this summer. I saw 39C (was there near to the end of Summer ) my hdd was 5400rpm ragular 2.5" hdd. Nothing happened everything ok!
A few weeks ago Ankara (the city I live) was seriously cold for its standards. I saw -10 in morning so I guess it went down around -17 or so; because I left a bottle of water in the car, and when I came back it was ice! That morning also my computer couldn't start. I have a handmade aliminum case and hdd is at the bottom of the case. So I heated the case with my lighter!! Now it works fine!!