SBQ suggested by Jan:

How many different brands of "complete" embroidery floss sets do you own? How do you keep track of it? (i.e., spread sheet program, index cards, palm pilot, etc.)

None. Everytime I near the end of the DMC list- they release more! I have most of the cotton, some of the rayon and linen, most of the light effects/metallics, and a few of the variations and variegateds.
The hand dyeds, like the GAST's and such I have only a couple of. Thanks to a RAK from Outi and the Odds'n Ends section of Silkweaver.
Let's see, I have several Kreiniks (all of the glow-in-the-dark, they were a must), and a few Anchors.... I think that's about it.
I keep track of them through an Excel list (spreadsheet program); well most of them. I haven't updated in quite a while. The Anchors haven't been added nor have the other ones I have only a couple of.
The Excel list helps me keep track of what really is mine. Nothing like buying a bunch of this or that for my floss kids, and then mixing myself all up as to whether it's in my stash or not!