If you want to sterilize your soil before planting your seeds, then put in the microwave. You will never want to use your microwave again for food, as the smell is unbelievable!
An old microwave is just great for the garden! I cannot remember how long to nuke your soil, about 2 minutes I think.
Must admit, been there done that. Long before microwaves and store bought potting soil, I used to bake my dirt in the oven on cookie sheets!
Just put it on the sheets and baked at 250 for a few hours, I don't recall a foul odor.
I actually do this a lot for growing fern spores. It depends on the composition of your soil on what it smells like. I rather like the peat/perlite mix I use. What I do is make sure the soil is moist (if not, it could catch fire) and put it in for 10-15 minutes. I leave it sit in the micro for the full half hour.
I sterilize seed starter every year. That allows me to re-use last year's starter. Of course, this isn't really dirt, but rather peat, vermiculite & perlite. You just want to maintain an inner temp of about 180 degrees F. for about a half hour. I use turkey baking bags, and there is just a minor smell from the vermiculite heating, I think... no swampy smells. Here's a link to my thread last year: http://davesgarden.com/t/202837/
I strongly recommend the use of a sterile soiless starter for starting seeds indoors. This really slims down the chance of 'dampening off'. Seedlings live off the cotelydons when small, so nutrients aren't needed in the soil until those die back.
I really think I'd rather be buried in the compost pile. That way, when my DH sits down to a meal of fresh garden produce, I'll be having dinner with him... of course the same could be said of Soilent Green! I can see most of the movie the old man watched by looking out my window... mountains, wildlife, eagles, etc.
I remember when my mother tried to sterilize her soil in the microwave while she puttered around in the garden. Lost track of time and ended up burning up the microwave. We were very lucky the house didn't burn down. She never heard the end of it! I guess there was some flammable additive in the soil.
This thread is very old but I just had to put in my 2 cents. Be very careful! You too could end up the laughing stock.
I just bake the soil in the oven. Doesn't stink that way. Plus you don't have to worry about buying a new oven/microwave. Just leave the door open to vent when done. If you are still skeptical, clean it.
I'd never do soil from the ground this way, but I've done soil and seed starting mix from bags a couple of times. I remember a smell, but I don't remember it driving me out of the house...and I'm sure it would have if it was that bad because that stuff can really bother me sometimes. I'd imagine that soil from the ground would stink a whole lot worse though.