I have one drawer of CD / DVDs that I haven't GCed in years - and possibly won't ever. That stuff is really a trip down memory lane. For example:
In addition to the agenda for Web TechEd 1998 (the only one ever) I also still have the post conference CDs plus it's accompanying system requirements correction letter: 486 or higher and 8mb of RAM.
Speaking of hardware requirements, here is another goldie:
Chicago SDK Kit, May 1994.
There's a lot more old stuff in this drawer, and I am not going to clean it out!