Also: IBAN (International Bank Account Numbers, 20-40-character account ids used mostly in Europe) - I just love it when I copy an IBAN (which legally can contain whitespace for grouping), paste it into a (length-constrained) input field, and the last third of the number is being cropped away.

IBAN fields should NEVER be length-constrained. Every country uses different lengths, and if you have a max length, chances are you are locking out some users from other countries (which actually is in violation of European law [Article 9, Regulation No 260/2012]).