defecation in strange places

I have a neutered one year old cat who has occasional pooping problems. He has gone No. 2 on the middle of my bed a few times over the year that I've had him, the last time being last evening. Then today, thinking it was because he wasn't getting his usual attention (I was very tired from working all day), I played with him, cuddled him and he still went No. 2 on my mat in front of the kitchen sink, while I was working at my computer. I didn't know until he jumped on my desk, dragging his bum across my desk pad. I thought he just had something caught in his long hair and when I took him to the bathroom to wash him I came across the doodoos on my mat. What is going on? Is this for attention? My litter boxes (I have two) for three cats, are in the bathroom and were cleaned out today. I am stumped. He is a very different cat - likes to be the centre of attention. If people come to visit he usually checks them out carefully and if he doesn't like them he hisses and stalks them. Is it just his emotional makeup?

I had the same problem last year, with my two year old female. After much advice from the ladies here, and a lot of trial and error, we concluded she absolutley did not like sharing a litter box. Soooooooo, we had to move hers in the basement where she had much more privacy, and we bought an extra box. We had about 4 accidents over 2 months time until we fixed it.
Now, I bought one of those Rubbermaid Totes, the really deep and large ones. I have just one for both cats and dont have any problems. I think the privacy issue was a big deal, as well as going to use the box and finding another cat in it.

Good Luck, I hope you fix it!