1996 Dodge Ram - I think I nuked the battery?

Hey folks - I have a 96 Dodge Ram that I use exclusively for plowing my own
driveway, and the rest of the year it sits in the driveway. As it's getting cold, I
went to make sure it was ready for the season, and as often the case, the
battery was dead (starter clicked / interior lights came on but wouldn't start). I
went to jump it, and when I was making all the connections stupidly
connected the negative black cable back to the batter, not the frame. When I
went to start it again, there was a small spark at the battery, and then after
that none of the interior lights / starter / anything worked, turning the key was
just silent.

I looked through the interior fuse box and saw the windshield wiper fuse was
blown (think that's been out for a while, those stopped working last year...)
but couldn't see any other fuses out, any sense for what else I should check?
Hopefully I didn't do something really dumb...

Thanks!