Keypress is a JavaScript utility (Apache‑2.0) for defining keyboard combos, sequences, and custom modifiers. Popular in game development and interactive web apps, it supports keydown/keyup, multiple modifiers, sequence combinations, and offers ~9 KB footprint with zero dependencies.
Library for building credit card forms and validating inputs
Created by Stripe and archived on GitHub, jquery.payment is a small jQuery plugin that formats credit card inputs—numeric grouping, expiry dates, CVC—as you type and validates card numbers, expiry, and CVC with client-side checks. While deprecated in favor of Stripe Elements, it remains useful for legacy implementations.