I'm a lot like bandicoot - my home is very tidy and "hoarder" is probably the last thing you'd think visiting it. However... I do have those tendencies. Growing up poor, we used what we could where we could. For years, I over-stocked cleaning supplies and canned foods, because that's what I remember running out of when we were kids. And milk - with two brothers, we were always out of milk. (Now I have two boys of my own, a tween & almost tween, and I see why!)
My biggest "hoarding" right now is paperwork. I have this deathly fear of throwing out some important paper/receipt/bill/whatever. Am taking drastic steps in the right direction: throwing out consumables receipt as soon as I enter them, being brutal with filing, taking advantage of scanner's PDF capabilities. I'm also using the Freedom Filer, which makes life easy and not so easy. o_O
Easiest thing? Being brutal with my kids' stuff. They have way too many tchotchkes (Zoar, you got it right! :) and fave clothes that don't fit anymore or have holes. (Mooom! This my favorite (insert clothing name here)! I don't care if it has holes! What stain? I don't see a stain?!) And instituting the one-in-one-out rule (if you buy/receive a toy, you have to get rid of toy(s) of equal size and/or value. It usually amounts to an entire bag of tchotchkes and a happy mom dance) has helped.
I will not raise hoarders. I will not raise hoarders. Aaaa-ummmm....