One good thing about cheques
The one thing I would miss if cheques became redundant is that it's the only elegant way to give a reasonable sum of money as a gift for, say, a wedding present or a birthday.
Sending someone a letter or a card with a cheque enclosed is a nice gesture. Sending someone a letter or a card with a note saying "I've transferred £xxx into your account" looks really naff. "I'd like to transfer some money to you - what are your account details?" is even worse.