I have directory for this. Every time I have a cool idea I create a simple text file with a name that tries to describe the idea and then in the file I type a description of the idea.
^^I do basically the same thing. I have shitloads of ideas in there. Some have the potential to be great and some have the potential to turn into nothing more than total shit. I say "potential" because I've learned the hard way more than once that many times what I think I know will be a grand-slam evolves into nothing more than a dog turd. Likewise, some things I throw up in an hour or less thinking "this will never amount to anything" will end up being gold.
Keep those ideas, though. Sometimes even the wackiest of ideas need to be kept around in a .txt file because as you learn and grow your business, you may one day come back across that idea and realize that somewhere along the way you just happened to pick up the missing puzzle piece that will make that bitch fly. Furthermore, I've sometimes been able to combine two or three ideas that, at first glance, appear to exist galaxies apart and would never "shake hands" with one another only find myself out running, in the shower, or on the shitter one day when the crucial "hinge" point comes to fruition in my head.
Sorry about the excruciatingly abstract concepts, but odds are anyone with any success in marketing has had to dig very, very deep in their "creativity tool bag" more than they'd like to admit to themselves. Falling back on those "Ah HA!" moments you jotted down a few months or even a few years ago can really save your ass in a pinch.
*Edit: I just saw that this was my 2,000th post on WickedFire. So not only did I shit the bed on not supplying boobs, I also can't shake the feeling that if I'd had realized this was #2,000 I'd have something more useful to contribute. If I weren't on the way out the door right now, I may have actually tried but since I am you guys will just have to settle for this. Apologies all around, boys and girls.*