I had similar thoughts about information sharing last fall when I was filling out grad school applications. All the forms were online, but I had to type in the same information (contact, academic history, etc, etc) on six slightly different web forms. And, maddeningly, even for the schools that had their application forms hosted by the same third party, there was no way to share my information between the different forms!
The first thing I thought of was "there should be a central clearinghouse of some sort, where I could fill out this once and have it shared between whatever schools I specify." But then (in a more free software inspired moment) I realized there already was a clearinghouse for all this information: me. Why shouldn't I be able to collect all this information into some standard (dare I say XML?) file format, post said file on the web, and then just hand people the URL when they needed that info.
There is XML Résumé. I had a look, and it looks simple enough. But as schwern pointed out, where's the Perl library