MS Paint also fails at Scaling things up.
Also, I now classify it as the second-best thing ever produced by Microsoft:
Windows 7 is my new number 1 (seriously! It actually works! Office 2010 is actually pretty awesome, too)

/0
Err:Data Type
Err: Invalid Dim
Err: Break
There's more, but I can't think of any atm

Don't forget to add error handling!

You're welcome, everybody.
You didn't the first time, Netham.
And how on Earth do I have more posts than you, Netham? You're, like, one of the first ones to sign up.

I HAVE A COLLISION ENGINE!
Ok. The ball size has changed (diameter is now 1 instead of 8 ) (the ball has a train behind so you can see it, don't worry)
Hold down * to leave a trail behind (which it bounces off of) hold down - to leave dots behind (which it also bounces off of) press / to clear remove all the dots and lines on your screen.
I think I've worked all all the bugs in the collision detection except one:
It falls through things when it stops moving.
I can't figure out why it's still doing this, so any help on working out this last kink will be the thing that finally gets xy off the ground.

GO! Download it now!
http://ourl.ca/10519/205534

I don't know much about Nspire programming, but I hear they haven't removed the 84+SE emulator yet, so here's what it would be in 83 series BASIC
ClrHome
Input "X0:",A
Input "X1:",B
Input "F(X):",Str1
Input "ITERATIONS:",I
{A,B->L1
For(Q,2,I+1
L1(Q)->X
expr(Str1->A
L1(Q-1)->X
expr(Str1->B
(L1(Q-1)A-L1(Q)B)/(A-B->L1(Q+1
End
L1

I can't figure out how to make it in Axe.
So I put it in The Axiom section.