I use my iPhone 4s and theapp AutoPano and in my amateur way am quite satisified.

Not the best but it got the job done.

Galveston Air Museum by Capisce, on Flickr

I, too, prefer to do stitching in post. The quality is better, plain and simple.

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I'm not lazy. I'm energy efficient.

I take the occasion to point out to anyone who have not tried it, to take a look at the free Microsoft ICE for every stiching / panoramic job. It's great, and absolutely easy to use: just shot a serie of frames, point the software to them, et voilà.

Microsoft Image Composite Editor

I have made a lot of panoramic photos entirely handheld, and it works very well.
It can also interface directly with PhotoSynth:

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Olympus E-P3 - VF-2 - Olympus 45/1.8 - Olympus 40-150 - Olympus 12-50 - Lumix 14/2.5

+1. Not to mention, I shoot 360x180s. :)

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MFT: G3, Panasonic 14-42, 45-200, & 20/1.7, Oly 45/1.8, Rokinon (Samyang) 7.5 fisheye; FL-50. Also lotsa Canon gear + MF lenses.
flickr stream and equipment list.