As an over-planner, I almost always buy more lollies than I need. This isn't a terrible problem (because I love lollies) but the time will arrive when I've had one Mars bar too many, and I'll need to get the sugary stash out of my house. The above popcorn cake is a great way to do that.
The recipe (linked below) calls for specific types of lollies, but pretty much anything will do. M&M's, Sherbies, and the like can just be sprinkled in, but whole bars can play as well, just chop them up beforehand. I would maybe stay away from gobstoppers though; you don't want anybody to break a tooth. (You could however, melt them down and drizzle them all over this situation.)
Once your cake of leftover lollies has been assembled and allowed to set, take it to work, give it to the neighbours, or just eat it yourself. I know that last one unravels my entire plan of "not eating lollies," but I'm just being realistic here.