I'm guilty of reading parenting sites like Club Mom and parenthacks.com just for ideas around the house and life. I always end up going to these from friend's posts, browsing around, and finding lots of information that can apply to anyone.
Here's what Erika wrote in the Quick Getaways Section:
"I buy plastic party tablecloths in different colors at the dollar store and make sure we keep at least one in the car. When the weather permits, we pick up a couple of sandwiches and have a spur-of-the moment picnic. A mini-party on a budget — with no cleanup!"
Not only have I experienced an inpromptu picnic but many other inpromtu experience have come from things I keep in my car. I never seem to have enough napkins though. I need to work on that.