So my wife wanted a bit of a wider lens than our 50mm for our 7D. I'm assuming she also needed a wide aperture, or she would have just used the kit lens (ours is super sharp, so I've been in no rush to replace it). People seem to really like the 30mm Sigma, so I went and added it to my cart, along with a few other odds and ends. Then I did a quick peek into the used section, and that's where it all started to go horribly wrong.

In the used section, I saw I could have a 5D for $150 more than the 30mm lens. There's the cheap full frame everyone wants! Sure it won't have the best high-ISO, and the resolution would be a bit worse, but I'd have a full frame! Our 50mm on the 5D would act like the 30mm on the 7D, solving the original issue, but also our 85mm and 70-300L would get magic transformations too. I'd get the choice of moving in with the 5D to get bokeh, and a perspective shift to get more background, or I could stay back with the 7D to minimize how much background is visible. I'd have a camera for when I can't back up, and a camera for when I can't get closer... All these options open up, for the same price as a low-end lens. Amazing.

The wife also wants servo performance. The 5D won't do that. Hmm. What to do?!? I kept looking.

For much the same price as the 30mm or the 5D, a 1DmkII was available. Several actually. I'd get a wider view, 1D build quality, portrait controls, and servo performance. But not the full focal length and perspective difference. In order to get the wider focal length, I'd still need to buy a lens. I didn't want to get a body along with a lens I can't use on it, so the 30mm was now out. I looked for a similar focal length fullframe compatible lens. Canon's 28mm is pretty close. It costs just a bit more. A 1DmkII along with a 28mm would work I suppose. But I wouldn't really have a fullframe, just a 1.3 crop, which isn't that different from what I've got. And I'd lose resolution. Phooey.

I'd gotten my heart set on a fullframe by now, the 5D wasn't going to cut it for servo, and the 1DmkII with a lens was getting expensive, and wasn't what I wanted. Hmm... What to do?!? I kept looking.

For much the same price as the 1DmkII and 28mm, I could have a 1DsmkII. I'd have fullframe, servo performance, 1D build quality, portrait controls, pretty much the same resolution as I'm used to (15MP with T1i, 18MP with 7D, and 16.6MP with 1DsmkII).

Add to cart, buy (and worry about it later). And that's how you turn a $500 purchase into a $1400 one.

So, am I crazy? Anyone going to follow me down the rabbit hole? You can do it cheaper with the 5D (both Adorama and B&H have used ones available in the $650-$750 range).