This is so weird.............I had that exact problem a few days ago, for the first time in as long as I can remember, too.
On a client virtual server I was remoted into.
I had recently installed a fresh Office 2010 desktop.
I started getting this error even when I made a new blank database and tried to drag a Combobox onto the form in design view - so obviously it had nothing to do with a specific database corruption (which at first was what I assumed as well).
My next step was an Office "Repair" (add/change programs, find Office, Modify, Repair), which did absolutely no good.
I then noticed I had excluded "Add Ins" from the Access install, so I modified the install to include that - also didn't change anything.
I then uninstalled Office totally, reinstalled Office, and things worked fine. Very scary stuff, considering that was about the end-of-the-road in troubleshooting to my knowledge.
If you can prove it's not isolated to one database but keeps happening on multiple 'new' ones...........try reinstalling Office.