1) Clean out your pumpkin, and wash the seeds well.
2) Fill a large bowl with enough warm water to cover the seeds. Add in enough kosher salt (regular table salt will work) to make that water ridiculously salty. Dissolve as much salt as the water will take. This is your “brine”.
3) Dump seeds in, stick the bowl in the fridge, leave them there overnight or longer. Maybe a second night. (longer is usually better, you want the seeds to really soak up that salt)
4) Drain, but DO NOT rinse the seeds. Spread them in a single layer on a cookie sheet (or two), and put them in a warm oven – around 200-250F – for a couple hours at least. Let them dry in that warm oven until they’ve reached the crispness that you want. Some might get a little brown-tinged around the edges, but you don’t want them to actually brown.
5) Eat the salty, crunchy goodness.
Update, 10/27/11: I’ve discovered that lining the pan with parchment paper helps prevent the seeds from sticking to the pan and browning on the bottom.