Dear University X
Dear University X,
Words cannot express my admiration for your environmentally conscious decision to eschew printed rejection letters in favor of a single "Dear Candidate" e-mail that you copied to all rejected applicants. Leaving the names and e-mail addresses of all the other 19 candidates visible helped to make me feel like part of a broader community of rejects. What a fun pay-off to the three and a half months of suspense during which you never even acknowledged having received my application in the first place!
Best regards,
Me
I'm glad I found a new job two months ago, or I'd have been feeling really upset and not sarcastic right now.

