It may be difficult to do, but this piece of advice is so true.

If you get an idea, write it down.  If you get in the flow, don't stop writing. 

Just like baseball player who's on a hitting streak, you have to strike while the iron is hot, hot, hot.

Because if you walk away, let the idea cool, there is the possibility you won't find that passion again. 

Then there is Elizabeth Gilbert's (Eat, Pray, Love) theory that ideas are driven to manifest. (Her word, not mine).  And if you get the idea and don't act on it, its going to move on to someone else until it finds a compatible human that will act.   It's an interesting concept. 

Got any ideas you want to write down now?