What is the best way to thaw the lug nuts on my car?

When the hubby tried to take care of my flat tire last weekend, he ended up crabby because the lug nuts were frozen, or maybe the tire was frozen on? I wasn't really listening, and I haven't looked at it yet. I told him I could wait 'til this weekend, he didn't need to worry about it during the week. Well, the thought of fixing it tomorrow is making him crabby again... so I want to get the spare on tonight while he's asleep, so I can take it in in the morning. (He wouldn't let me do it otherwise...darn men!!) So question, guys out there (and girls, too!), are there any secrets to unthawing it? It's -7 degrees out there now. Would it work to just set a space heater up? Or is there some secret like spraying antifreeze on it? I'd like to spend the least time out there as possible tonight. (brrr!)