Dock popups

Every so often, a few of my dock icons will popup in middle of screen. These are larger icons of some which are present on the dock.What is causing this and how to get rid of them? Thanks for amny suggestions. Van

Some of the icons? Like the apps currently in use?

Are you hitting cmd-tab by chance?

popup dock icons

The ones that popup are the same ones on the dock,None of which are in use.
If I click on the large opp up icons, nothing happens,and no, I'm not hitting any other keys.

If you're using a Mighty Mouse, inadvertently pressing the scroll wheel or side buttons may cause the App Switcher to appear in the middle of the screen. This will always have at least the Finder icon on it, and any other apps that may be running without your knowledge. (For instance, you may have closed an app window without actually quitting from it, so it's running without being visibly "open". This would appear in the app switcher.)

That's the only thing I can think of. My MM sometimes registers any bit of pressure I put on it as a "click" so that my app switcher appears momentarily. Sometimes I see that iCal or something like that is open because I forgot to actually quit it last time I used it.

Oneironaut,
I think that was the problem,I never knew the Mighty Mouse would do that.
Thanks for the suggestion. Van