For arbitrary precision mathematics PHP offers the Binary Calculator which supports numbers of any size and precision, represented as strings. This project replicates this in JavaScript (bcadd, bccomp, bcdiv, bcmul, bcsub, etc)
JS-BSC is a JavaScript Bowling Score Calculator that also shows max possible score for the game, as well as an interactive per-frame pin knockdown diagram. Tracks 1 game for 3 players, or a 3-game series for one player (easily modified).