In a similar vein, I found it momumentally difficult to throw away the two cardboard boxes that contained all of my lecture notes, papers and exams from college. I had dragged them along for a couple of years after I graduated; sometimes thinking that, yes, these will be valuable reference material when I go back to grad school (which I never did anyhow.) Of course I now realize that that was highly specious reasoning since my lecture notes weren't very helpful as references even when I was in class.
Finally, one drunken night I decided that my boxes of lecture notes were no longer a useful reminder of my academic achievment and more of an albatross around my neck. After all, my job at the time (opto-electronics) had almost nothing to do with my college major (straight physics). So I dragged those two boxes down the stairs one last time and put them on the curb to be picked up by the recycling guys. Honestly, the next morning I had to stay inside until my notes had been picked up because I felt an incredible urge to run outside and save them. But I was able to resist and now I'm glad I did because I feel that much freer.
And if I ever need a reminder of my college successes, I still have my diploma. Somewhere.