Why would you want to have so many fonts?
Imagine you would have all the fonts from http://www.dafont.com, that are around 8500 fonts.
(1) It would slow down your system immensely. I don't know how long it takes to load a font, but I believe loading 8500 fonts will cost a disturbingly long time
(2) At 70kB per font file, and in general 2 or 3 font files per font (bold, cursive, etc.), this is almost 1.5GB of fonts. Personally, I know better uses for my bandwidth and storage...
(3) If you use 2 new fonts every day, which is very unlikely, you will need over 11 years to use all these fonts.
(4) Don't overestimate the importance of fonts. Everyone involved in graphics editing or webdesign will tell you the same: having too many fonts in one image/website gives an unprofessional impression. Moreover, you can do almost everything with the basic fonts you already have. In the maybe 5 years I've been doing things like this, I have downloaded maybe 10 fonts (like 1 gothic font, 1 eroded font, 1 lcd-digits font etc.).