I pretty well started collecting from since I was a little kid, so about 25 years, although most of my collection I've gotten just in the past 5 years or so. I do like "micro-collections" which makes it a bit easier, it's less daunting that way and doesn't seem completely impossible. You get a much greater sense of accomplishment too out of it, as most of the "micro-collections" can be achieved in less than a year and don't cost too much money. One of the "micro-collections" I most recently started gathering was for mail/package pieces, which is just about complete:
I think the only one I'm missing is the present/gift box from that newish Christmas village set.
-EDIT-
There's actually some others I could include with this collection, like that one brown sack/package tile from the Harry Potter sets. And that other tile with bed roll pattern. I could also include that yellow 1x3 brick with the cargo pattern on it.
