121 is a palindrome, a phrase that is the same spelled forward or backward.
Find two of them from the Palindrome list site that make sense in a tweet.
Delia saw I was ailed. Oh, cameras are macho.
See also, just because it is interesting, a video that plays with this idea
Tweet your palindromes to @agoraUdG and be sure to include the hashtag #agoratry121
Don't Want to Tweet Your Response? Really?