Right now I keep my MR collection at my desk since my current living situation is temporary and it's the only space I have for it. I've been a big fan of the series since '97, and I have the complete set of the 1999 Playmates figures and the larger rubber figures from Japan! I'm slowly hunting down the Jack Egg figures from Argentina as well as some of the chibi/SD figures from Japan and Hardee's/Carls Jr. happy meal toys (I only have golem and Tiger so far).
I also have a Monster Rancher ita-bag and a growing assortment of fanmerch I'm filling it with.