I accumulate books and DVDs, I don't collect get them to have, I get them to obtain information, so I don't know if I'd really term it collecting for the sake of collecting.
I collect small, very varied trinkets featuring rats, anything from Chinese carved jade to Indonesian bone to American pottery. I don't care where it comes from, so long as it's cute and has a ratty on it. I love me some ratties.
Australian lustreware vases made between 1940 and 1960. I find the vases in themselves beautiful, but I'm also fascinated by the slow drip of information that I've been getting about the different potteries that were making these vases. There's very little information online, and while a couple books have been written about those potteries, they were published in runs of 1000 or 500 and have been out of print for a decade. So whenever I uncover a new scrap of information or find a new maker it's like I've won a little prize.