So, I was making a website as a favour to a friend of mine. The site has a gallery (not published at time of posting). Like any gallery, it has simple needs: a bunch of thumbnail images, and then a bunch of larger images conveniently sized for viewing in a browser.

It turns out there are three ways of doing this:

1. Manually: open each image in an editor, size it to two different dimensions, save the edited versions. This is slow, boring and laborious.
2. Using a desktop application: find a batch feature in one of my existing image editors to do it, or get a custom gallery-making program to do it for me. I know Paint Shop Pro has this feature, though it requires a little fiddling to get right. I'm only getting to grips with Photoshop quite late in my web development life (Paint Shop Pro always did everything I needed, and still does, but Photoshop is what Yahoo! has a license for), but I assume it can do this too, possibly involving downloading some sort of macro or something. I'd have to google it to find out.
3. Using a web service: as it turned out, the easiest way to do exactly what I needed was just to upload the images to Flickr. Flickr automatically produces several sizes of image, including thumbnails that are cropped to better show off the content of the photo. This didn't involve downloading anything and was by far the easiest method. And as a bonus, the Flickr community now has some images of the performers tagged with the event name.

This is important because of what it says about how people will use web applications: not because they particularly need portability or central storage or any of the "web" aspects of the service, but because the application is easy to use and does exactly what they want. It's only recently, as average bandwidth has increased and interfaces to services have improved, that it was at all possible that a web service would be a better user experience than a dedicated desktop application. But this is where, eventually, almost the whole application space is going to go. That's been the consensus amongst the kind of people who make it their job to think about these things for a while, but it never really struck home for me until just now.