lol, Bill you seem like a nice guy, but if taking a shower is a luxury, I don't know that I'd want to meet face to face ; )
Peanut Butter = luxury is sad, but true, and because of it's difficulty to get it's a much coveted item (sounds like I'm talking about diamonds or oil, eh?)
Computers should look like they are personal, ie used at least a for a bit. Take it out of the box and get some files on there -- otherwise you may fall prey to the occasional customs guy that makes you pay import duty on it. The last time I came through my laptop was 3 days old, but I had transferred all my old work onto it so no one could accuse my of just picking it up.
If you're bringing in bigger items, like monitors, again best if it looks used -- which I guess for a monitor means a bit of goop on the edge and some fingerprints on the screen where you touch it? lol, who knows. You may have to pay duty -- I haven't tried this yet. I need to get a new moni, but I'm going to order one through Dell Argentina -- their widescreen LCDs have very good reviews and the prices are very similar to Canada, and I think their delivery time is 3 days.
By the way if you need to buy any computer related gear while you're down here (ie if you're in a jam and don't want to wait until you get home) go to Galleria Jardin on Florida for the smaller stuff (external HDs / HD USB converters, HDs for laptops are a lot more expensive for the size you get, but you can get quality ones there in a pinch, cables, routers, keyboards etc etc) -- for the bigger stuff (an OS, Monitors, PCs etc) skip Compumundo and go to Baidat on Juramento.
www.baidat.com.ar (there's a Compumundo on cabildo around the corner anyway, so you can comparison shop)