A general rule for hoarding mass annual freebies is that the items that are usable aka limited and declining quantity, but still usefull, will inflate over time, the more useful the item the faster and more expensive.
If I were to do it I would horde things like books, 1 time bdome weapons that are useful (those muffins that time).
Edit: Forgot, for this to be profitable you generally need to buy lots of the item, so say it just came out and its at 800np, if u buy say 100 of them, then in "time" they will go up to 4-5k or w.e.. then you made roughly 3-4k x 100 (for essentially doing nothing) and legit
Edited by Jackle, 04 March 2010 - 07:40 AM.