You must know you are pushing the bounds of reality
Try lighting a large room (like a hotel foyer with a sea view) or using a large softbox with a 4AA battery powered flash...
Why would I suggest you use speedlights for architectural photography, especially in the situation you suggest? Though of course lots of small flashes that can be hidden when there's no room to have larger stobes could be very handy, plus you don't have then remove all the power cables that may be in shot. Sometimes the 'wrong' kit can be better than the right kit!
or even a dancer jumping..[a href=\"index.php?act=findpost&pid=141700\"][{POST_SNAPBACK}][/a]
Do you mean this pic?
Personally I like to shoot just available light, but in this case I ended up shooting with the single flash I had with me [and was still learning how to use] to try and balance Joseph's very black skin against a very bright background. I had only just started using digital at that point, so it was all a bit experimental. Canon Flash exposure is a little erratic at times and I got the best composition with one of the worst exposures. Having said that it was printed and used in an exhibition in Sweden recently and it looked fantastic, it looks better printed than on screen. That's a very old version of that shot on website. I actually have a completely new website as well that I did last year, but stilll haven't had time to fill it up and put online. But that's way off topic.
Not sure why some posters are thinking that speedlights are replacements for studio lighting. I simply mentioned that they can do much faster syncing than some people believed that's all. Which allows for shots not possible with MF and studio flash. That particular shot is not even using the high speed mode, it's shot at 1/250th. If I'd known how to set the faster sync then, I would have done so and used the flash on a lead held above my head, which I did not have at the time. But even though it's not technically perfect it's a very popular image.
If I were to shoot it now, I would like to use studio lights with a H3 and have some Sherpas to carry the kit for me - it's a long walk away from any car parking! We cycled off road to get there.
At Herrang in Sweden, this year a photographer from NY Times turned up to do an article and used studio lighting on the dance floor to photograph freestyle dancers and made himself very unpopular by doing so. And then by virtue of being fixed in place, when something unusual and more interesting happened in a different part of the dancefloor, he missed the shots completely.
I'll repeat something I said earlier, a hammer, saw and a screwdriver are all great tools. When used at the correct time. Speedlights, Strobes, DSLR and MF DSLRs are no different. All are brilliant tools
when used appropriately.