This guide is mainly for Logitech mice, since I and majority of people use them. Also, I only know how to do this stuff with the Logitech mice.
For samples and stuff, I'll be using my Logitech LX5 mouse, but I'll add details on more advanced mice too.
Also, I'll be using my good old computer for screenies, annotations and stuff, so y'all now that all this stuff is real and not made up 
Oh another note: I won't use the "Game Mode" in SetPoint cos it's not working quite right with my mouse.
So, let's begin.
First, you'll need to download and install [URL=http://www.logitech.com/index.cfm/support_downloads/downloads/&cl=roeu,en]Logitech SetPoint[/URL], if you haven't done that already.
When youre done, launch the sucker. (The link is called "Logitech Mouse and Keyboard Settings" btw)
On the left side - your mouse, in the middle - the buttons, on the right - options for selected button.
Simple, no? Yes.
Now what do you do:
Leave the left & right click as they are. YOu'll need them (Well, unless you're left-handed and want to switch left/right button)
The big deal (in my case) are the middle mouse button and wheel tilting sideways.
This is only how I do it. Feel free to experiment
This can be done inside FL Settings -> Controls
FL recognizes the middle mouse button (at least for me) as MOUSE3 so there are no problems. If it doesn't for you, read on.
You can use ANY keystroke you could use in FL, and even more
Now about the tilting - FL won't recognize wheel scrolling left/right so you have to use "keystroke assignment" option and assign the tilting to a button in FL
For example, if I set left tilt to CD launching, then I input the key I use in FL for CD launching. Simple, yes? Yes.
The same goes for right tilt, only I set it to CM launching.
Why do I think wheel tilt is the best for CMs/CDs? Cos you can push the wheel always with two fingers (either index or middle), so it's always reachable and tiltable. Also, the tilting is easy, because the distance to tilt is ~0.5mm
Also, the "Game Mode" should let you make custom assignments for each game, but I dunno about that, since it's not working for me 
I have to manually reassign every function for normal duty after gaming 
[size=3]More advanced mice[/size]
This chapter is purely fictional and from my mind as I can't test anything I wrote below
MX Revolution
My suggestions are:
G9
Well, folks, that's it for now I hope that you can be creative enough and use at least something of this for your own mouse.
If this small tut helped even a bit at least 1 (wo)man, then I'm happy
Coming soon: [Really] Advanced Keyboard Config for FL 
Also I'll tell you how to make FL do SHIFT/CTRL/ALT+MouseClick (if I can remember) [for example: Middle Mouse = reverse, SHIFT+Middle Mouse = engine kill]
Brother Azy did it with his snake.
