Terms used for getting junk food, mostly by street people and people in jail. Was often used when someone would spend a $1.00 food stamp and get the change back in coins. The items bought based on how cheap they are but they still bring happiness. In jail they are used for negotiation and trade.
When you really like someone and things are going great, and then you suddenly don't like them anymore for no apparent reason, or start to find miniscule things that are with wrong with them that annoy you.
"Tom and I went on 6 dates and I was really starting to fall for him! Then I got the whim whams."
"I really, really, really like Michael, but... I've got a case of the whim whams. I decided that I actually don't like his beard or his cat or his shoes."