So rather than a random number generator, this is a random code generator. It's a fairly simple program that generates random characters. I actually ended up putting a little extra work into it than I intended to. Making it generate random characters was a lot easier than I thought it would be, so I added some extra things as you can see in this screen shot:
Spoiler
As you can see, I've generated a random hexadecimal code by disabling all the characters irrelevant to hexadecimal numbers, with the default number of 18 digits, which can be changed by using either the arrow keys, or by clicking on the arrows on the screen. The code disappears after it appears mainly because I imagine this program could make a good random password generator.

Here's the code:
http://pastebin.com/seyTaa0k

The code is pretty simple, like I said, this wasn't as hard to make as I expected, and it's probably nothing special, but I figured I'd share it anyway, because I think it's pretty cool and probably useful. :P/> This program is an extension to an 18 digit random number generator that I never shared, which is literally only 4 lines of code that exist in this program, though slightly changed to suit this program's needs. This is the old code:

local RNG = math.floor(math.random()*10^18)
print(RNG)
event, button = os.pullEvent()
shell.run("clear")