Someone Please Answer This One

this one is a simple question, but its needs some bit of thinking.

so you have a client. you design him a website and a CD… everything come out great. you give him the .SWF files and the projector, he gives you the $$ and everything is good.
Untill that one day, when he ask’s for the .FLA! now I as a designer do not like the idea of exposing my clients to the source file(.FLA)

what do you guys think?
Am i right or am i right? which one is it? are there other designer in flashkit who feel the same way about given their source file to the clients. am i sure there some of you, who would agree…
i mean hey its your hardwork and you got the job done. to give away the .fla is giving away the functionality of your work, which therefore would let your client pratise and improve his own flash skills.

Should i charge him, extra for purchasing the .FLA from me.
Should i give it away for free?
Or Should i just mess up the the .FLA and then give it to him… … i know i know that would not be ethical, but i would believe it would be pratical…

please guide me , you guys do a great job at it…

Tough one, as said before depends whats in the contract. If the contract says build a site. then the swf is fine. If you make gifs for them do you own copyright on the gifs?

Just think of it like this, would 2A or []WA007 or []FI give out their source files? If they did then we would all know their secrets. Just tell the client that you can’t give him the file 'cause you don’t want people to know how you make stuff. If he says something like, “But I won’t tell anyone”, just make something up or tell him no anyways…:thumb: - just my 2 cents.