My mind is still a little boggled by this, but I'll try to explain it the best I can. Last night, I opened up the Quicksilver preferences to see if there were any new plug-ins available (in the new Tiger version, you get plug-ins from an internal menu rather than from their website). Specifically, I was looking for one that would allow me to ftp a particular file to a particular location (check out my last post to find out why).
Some new plug-ins had appeared (including the del.icio.us one, which I'd been waiting for), but nothing for ftp. One of the new plug-ins was called "Services menu module". Immediately, the hairs on the back of my neck stood up.
You see, a while back, I downloaded a little app called Text Wielder. What it does is make avilable more than 120 actions from the Services menu of every application. Most of them act on text: get a URL, search in any number of search engines, look up a map from a given zipcode or a zipcode from a given address (I think that one was why I got it in the first place), etc. You can also write your own actions.
So now that I can use any applicable service from within Quicksilver, I have all of these actions at my fingertips at all times. So, beyond having solved my instant-ftp problem (Transmit.app offered "upload file" as a service), I now have a very deep pool of things I can do with text (the number of options on text went from in the teens to 89). Plus I have the ability to create any new actions that I want, so the pool is actually theoretically bottomless. Just when you think Quicksilver's run out of new ways of blowing your mind, it finds those last few shards of attached skull and sends them skittering.