Long web pages are very common in this age of planets and forums and it becomes annoying to scroll the mouse wheel multiple times to go up and down these pages. Firefox does not have the extravagant preferences interface as its venerable big brother to change the number of lines the mouse wheel scrolls on a page. In case you want to change/increase the number of lines scrolled with the mouse wheel all you need to do is to change the following settings in Firefox's about:config.
mousewheel.withnokey.numlines -> 5
mousewheel.withnokey.sysnumlines -> false
The first option controls the number of lines scrolled by one mouse wheel scroll event (default is 1). The second option tells Firefox to use the system's number of lines scrolled by the mouse wheel scroll event. So to remove the dependency on the system settings, I changed it to false (default is true). After these changes, try scrolling a long web page and see the decrease in amount of effort it takes to go down the the bottom of the page.
Happy scrolling :)
PS: Bought a basic optical Microsoft wireless mouse on a deal for $9.99 as a replacement for the last roller-ball mouse on my music server.