Since you like building things, how about a Mini
WSM?
I agree times 10. The mini is about the most versatile portable cooker out there. Ok, I don't have firsthand personal experience with EVERY portable smoker, but I would put my mini up against any one of them head to head without fear of defeat. It's that good. I've said it many times on here (I know, I sound like a broken record) but I've used it as a grill, smoker, oven. stove, fire pit and probably other uses I'm forgetting. I've taken it camping, to friends' houses, on vacation, to parties, to the park....
And I drive a Miata! When you're done cooking, just pull the tamale pot off, put the lid on and clamp it down, close the vents and within 15 minutes it's cool enough to put in the car.
I've cooked everything from a small batch of ABT's to pork butts, salmon, chicken, peach cobbler, biscuits, ribs--all the way up to a 15 lb. turkey and with the exception of one disastrous chicken cook (my fault) it's been FLAWLESS. It will hold any temp from under 200˚ up to and beyond 375˚ LIKE A CHAMP. On a full load of coals, you can easily get 4-6 hours depending on conditions and your target temp.
Just tell your wife to write out an authorization for you to gather the parts and build it and let that be your Christmas present. You can get everything for well under $100. By the way, if you want it to be portable, go for the Smokey Joe Gold. The Silver is slightly better for grilling, but the Gold has the lid clamp and side vents which make it the perfect portable smoker. The Gold does fine for grilling, the Silver just generates a little higher temp due to the airflow directly beneath the coals.