What's hap-pen-ing to me?

I'll be darned if I know where my pens are going. Yesterday, I couldn't find the one I had been using all afternoon. I looked every place I had been, and even under the furniture. This morning, I came into work and couldn't find the one I always use and always put back in the same place. Thankfully, I use only cheap, disposable pens, so at least I haven't lost too much money.