Power saw. I keep wanting to cut wood, make canvas frames (I paint), the odd little project here and there. I have a hand saw right now.

But I just recently went through this on another item and it's a great story (at least I think it's mildly amusing):

A full and proper socket wrench set. I had two small crappy sets that, together, made a full set kind of. They wouldn't stay in their places in the cases, had to search for 3 minutes to find the one I wanted, had duplicates of some sizes, missing other sizes but I always made it work even though I usually had the wrong one or had to rig something up. I finally decided one day that I was sick of this monkeybusiness and that the next time I was in a store and saw a nice set that I was going to buy it no matter how much I argued with myself.

The day finally came. Saw a nice set, all the sizes I needed with loads of screwdriver bits and other awesome things, nice case. Very nice. I put it in my cart, walked on for about 5 minutes before arguing with myself to put it back. In the middle of that, I had to laugh out loud because I had already known that I would argue with myself about it. So I shut up and bought the damned thing. Haven't regretted it since.

Same thing with a cordless drill. Didn't have a drill, just a dremel. Made it work for just about everything. Now that I have a drill, my repair/project life is so much easier. I have no idea why I was fighting myself buying one except the $70+ pricetag.