Well, I promised it, so here it is.

Toss this Actionscript into Flash with a background movie clip called 'background' (creative huh?), and you'll be able to scroll around with your mouse to your hearts content.

Making this tutorial was actually useful for me as well. While I was trying to explain myself and simplify the code as much as possible, I found new ways to do different things that made things much easier. So what you see is the 'refined' version of the mouse movement, not the hack job I made before.

As with all my tutorials (2 so far) play with them and feel free to use them in whatever you make.

Enjoy!

ONLINE EXAMPLE (be patient as it loads because there is a large background image)

ACTIONSCRIPT:
// Variables
var mousePositionX:Number = 0;
var mousePositionY:Number = 0;
var speedX:Number = 0;
var speedY:Number = 0;
var edge:Number = 125;
var scrollDivide:Number = 10;

// Event listener for movement.
stage.addEventListener(Event.ENTER_FRAME, calculate);

// Function for moving.
function calculate(Event) {
mousePositionX = mouseX;
mousePositionY = mouseY;
// Left edge.
if (mousePositionX >= 0 && mousePositionX < edge && mousePositionY >= edge && mousePositionY < (stage.stageHeight - edge)) {
speedX = (edge - mousePositionX) / scrollDivide;
background.x = Math.min(background.x + speedX, 0);
}
// Top left.
else if (mousePositionX >= 0 && mousePositionX < edge && mousePositionY >= 0 && mousePositionY < edge) {
speedX = (edge - mousePositionX) / scrollDivide;
speedY = (edge - mousePositionY) / scrollDivide;
background.x = Math.min(background.x + speedX, 0);
background.y = Math.min(background.y + speedY, 0);
}
// Top edge.
else if (mousePositionX >= edge && mousePositionX < (stage.stageWidth - edge) && mousePositionY >= 0 && mousePositionY < edge) {
speedY = (edge - mousePositionY) / scrollDivide;
background.y = Math.min(background.y + speedY, 0);
}
// Top right.
else if (mousePositionX >= (stage.stageWidth - edge) && mousePositionX < stage.stageWidth && mousePositionY >= 0 && mousePositionY < edge) {
speedX = (mousePositionX - (stage.stageWidth - edge)) / scrollDivide;
speedY = (edge - mousePositionY) / scrollDivide;
background.x = Math.max(background.x - speedX, stage.stageWidth - background.width);
background.y = Math.min(background.y + speedY, 0);
}
// Right edge.
else if (mousePositionX >= (stage.stageWidth - edge) && mousePositionX < stage.stageWidth && mousePositionY >= edge && mousePositionY < (stage.stageHeight - edge)) {
speedX = (mousePositionX - (stage.stageWidth - edge)) / scrollDivide;
background.x = Math.max(background.x - speedX, stage.stageWidth - background.width);
}
// Bottom right.
else if (mousePositionX >= (stage.stageWidth - edge) && mousePositionX < stage.stageWidth && mousePositionY >= (stage.stageHeight - edge) && mousePositionY < stage.stageHeight) {
speedX = (mousePositionX - (stage.stageWidth - edge)) / scrollDivide;
speedY = (mousePositionY - (stage.stageHeight - edge)) / scrollDivide;
background.x = Math.max(background.x - speedX, stage.stageWidth - background.width);
background.y = Math.max(background.y - speedY, stage.stageHeight - background.height);
}
// Bottom edge.
else if (mousePositionX >= edge && mousePositionX < (stage.stageWidth - edge) && mousePositionY >= (stage.stageHeight - edge) && mousePositionY < stage.stageHeight) {
speedY = (mousePositionY - (stage.stageHeight - edge)) / scrollDivide;
background.y = Math.max(background.y - speedY, stage.stageHeight - background.height);
}
// Bottom left.
else if (mousePositionX >= 0 && mousePositionX < edge && mousePositionY >= (stage.stageHeight - edge) && mousePositionY < stage.stageHeight) {
speedX = (edge - mousePositionX) / scrollDivide;
speedY = (mousePositionY - (stage.stageHeight - edge)) / scrollDivide;
background.x = Math.min(background.x + speedX, 0);
background.y = Math.max(background.y - speedY, stage.stageHeight - background.height);
}
// The middle.
else {
}
}