I like to pick up nice looking lavender items. I don't buy all of them, but whenever I see one that doesn't look bad I'll immediately put it on my wishlist to purchase later. It's a habit I got into when I picked up the Fluorite Borealis years ago, and struggled to make it work.
I LOVE LOVE LOVE items that have a pink/white color theme. (Like the most recent rei~heart) I must have ALL the pink/white items. I also have a fondness for items that are designed around sweets/desserts themes. (Keiko's Cake)
But you know what I REALLY want more of? MORE ULTRA SATAN. I would pay millions of gold for more ultra satan swag.gonk
Ah, I too have a background addiction! There are some I can resist, but it really depends. A generic beach background is easier to pass up, I've got three. But city backgrounds? We don't have a whole lot of them, if a new one comes out I just gotta get it! cat_rofl
And, mermaid tails. I collect mermaid tails and currently have all of 'em. If a new one comes out, I need it to keep my collection full.