We kept it simple, using only 1 to 10, where 1 can be treated as 1 or 11 (as an ace).
Each player "draw 2 cards":
e.g.
/random 1 10
Fyrx has draw a 5 between 1 and 10.
/random 1 10
Fyrx has draw a 9 between 1 and 10.
So I have 14.
Then everyone takes turn drawing until they stay, or bust (over 21). Once you hit a number that you are happy with (and not bust), you say 'Stay' and that will be your final score for that hand.
e.g.
/random 1 10
Fyrx has draw a 1.
I now have 15, and can stay, or hit.
if I hit again.
e.g.
/random 1 10
Fyrx has draw a 7.
I would have 22, and bust, and lost that game.
If everyone bust then it's a tie.
Tie also for players with the same highest score.
Recommend pooling munnies into a pot and winner take all for it to be more fun

I was trying to think of other games you can play using the random command, but I am fresh outta ideas.
Throw some at me.