My Problem:

I have a lot of unsorted scientific papers! Their filenames don't resemble their titles and they are stored in a bunch of places. I tend to download them as I search the internet for papers that help me with a problem and sometimes I even DownThemAll.
Weeks, month later, I try to find the *one paper* that was so interesting and cite it via BibTex in my Latex file. But I can't remember the filename, title, author, year or journal (in any combination).
Or I see a paper, know that I read it, but can't remember if it was that good...

Possible Solution:

Using a search engine (Tracker), a bibliography manager (Referencer) and a file manager (Thunar).
With Thunar, I can mark files as interesting.
With Tracker I can search the text of a document and tag it.
With Referencer I can tag a paper and export the meta-information to a Bibtex file.

Why I'm still unhappy:

It seems that Tracker, Referencer and Thunar don't use the same location to store meta-information about the documents. They all seem to use different databases. I would have to write a plugin for two of them to get the three of them working together.
Not good.