The image on my home page has been seriously tweaked from the original.  Here's the final result:

_SK_6943

And the original:

Interesting, eh?

Image shot with a Canon EOS 1ds iii using a Canon EF 8-15 fisheye lens. Processing in Lightroom 6.

Adobe Lightroom incorporated a "de-fishing" tool (actually applying a lens profile) a few versions ago, and it's been getting better and more aggressive over time.  (Us de-fishing afficionados have been using tools like ptlens to do this, but now everyone can get at them!)  Simplying applying the lens profile does a pretty decent job, but the really fine work involves going into manual mode and working the vertical, horizontal and distortion settings to make the lines ruler-straight.

There are tradeoffs, however.  De-fishing can severely warp objects in the corners (and spread the pixels out a bit, so you might lose a little resolution on the margins), so a fair bit of subjectivity (and subject matter selection) is necessary.  For example, if any people were close to the lower-right or lower-left corners, the picture would have looked terribly unnatural.