While it is an expression of at least a moderate amount of manual dexterity, thumb twiddling is frequently used as an example of a useless, time-wasting activity.
It is equated with other activities that are also considered useless by the speaker. Therefore it is most often used as a synonym for an activity that will take the attention of the performer, but will not yield any useful results.
(all information "borrowed" from Wikipedia)
Sure, there is more that I could be doing right now than obsessively checking any blog related to (self-reported) MFA acceptances...I am being a somewhat productive member of society...especially now that I'm not watching the Winter Olympics (I think I deserve a medal for my fanaticism).
I go to work.
I communicate with friends.
My sweet Buttercup gets a lot of love.
I could clean my room.
I could clean my car.
I could read a book...or maybe WRITE something...
But I check blogs instead.
I wait and wait and wait. I'm to the point of chasing the Mail Truck around the block...and don't ask me how many times an hour I check my BlackBerry just to see if maybe I have e-mail...
I'm an incredibly lucky person already. I've been accepted to a prestigious creative writing program, but the funding (TA selection process) isn't a guarantee. I have to wait...
I have two official "NO's"... so I'm waiting to hear from SEVEN schools (in case the funding doesn't work out).
& learning about Thumb Twiddling (of course):
- Most people tend to twiddle their thumbs in the direction where the thumb currently at the top goes towards the fingers.
- Twiddling the thumbs in opposite directions from each other is significantly more difficult than regular thumb twiddling.
- Thumb twiddling can be used as a simple test for manual dexterity.