Simple enough...post examples of images taken that otherwise couldn't have been without IS or a tripod available (shot using IS, of course). The question is not what you can do for IS, rather what can IS do for you!?
I can't get you distinct pictures, but if one goes to my flickr account (www) and looks at my recent vacation photos, most are taken with the 24-105 is lens.
A lot of the interior photos are shot at f4-f5.6, iso1600, and shutter speeds longer than 1/8 of a second. Traveling with a tripod is a pain, and IS helps a absolute ton.
Most of my recent pictures benefited from IS. As a matter of fact, 70-200 f/4.0 L IS is my lens of choice for low light situations (if I do not have to take "action shots"). At the same time, I also use primes without IS if I need higher shutter speed.
I posted a few of my pictures recently so I am hesitant to re-post them here. I have sharp (hand held) pictures taken at
1/15-1/20 for 135 mm
1/30-1/40 for 200 mm
1/40 -1/50 for 280 mm
I love having IS on telephotos for zoo trips and the like. I generally don't like taking a -pod to the zoo except in the off season, simply because there are too many people (especially smaller children) running around and getting in the way.
Anyhow, this is not the best example, but it is the best I have on hand. I believe this was the 70-200 f4 IS + 1.4 TC. I stopped down to f9 to get a little DoF, and the shot was 229mm (366mm effective on the 40D) at 1/20.
I much prefer to use a tripod with telephoto lenses. Even so, I would not consider buying a non-IS lens if an IS lens is available. I bought a 300 f4 L IS years ago, and use it 99.9% of the time on a tripod, with IS off.
But I recently went to my first rainforest (Madagascar), when the thick foliage made careful tripod setup time, to avoid leaves, too long to be practical, on rapidly moving lemurs.
If you do an internet search on lemur pictures; the average posted picture quality is so incredibly bad, that you can’t tell if you are looking at a lemur or a house cat! That is because the light level is so low, that hand held photography without IS is impossible, and most pictures are radically underexposed.
Below is a large lemur photographed at about 40’ away, in a fairly open area with higher light levels than the average Madagascar rainforest. It was taken at 1/125 sec at ISO 800 with no noise reduction applied. The first picture shows the overall scene, and the second 100% crop shows that the hand held lens can effortlessly resolve a single hair on the lemurs butt! Try that with a hand held non IS 300 lens! More than 90% of my rainforest pictures would have been impossible without IS.
That shot turns an extremely difficult exposure into a most realistic amd plausible image.......brought to mind the times when I was on a ship sailing similar rough waters.
Yes, it was at 400mm. I shot a big burst at max fps and this was the sharpest of the bunch. I doubt any would have been sharp without IS. I can routinely get sharp shots at 1/50 if I concentrate on good technique.
Nice shots Stan but I need a lot more assurances of choppy waters in small Zodiacs Stan that big boat looks awful familiar to me. Ioffe Akademik? When did you go?
As you can see in a shot I took in December 2006 waters weren't quite as choppy. Coming back to SA it was Lake Drake not the Drake Passage
Thank goodness it wasn't as rough we had weight restrictions of carry on luggage then , so my 4 lens I took all were non IS
17-40
50 1.0 (yes Peter the 50 1.0 you want as a backup went to Antarctica )
70-200 F4 - I wish that Canon had the IS version available when I went
400 F5.6
Stan that big boat looks awful familiar to me. Ioffe Akademik? When did you go? 
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