For several years now, Austin has had the slogan, "Keep Austin Weird."
This was adopted by local small businesses in an effort to encourage
people to buy their goods and services locally. The phrase even made it
onto A Prairie Home Companion when the show visited Austin.
There, Keillor's character Lefty speculated that Dusty had read the
bumper sticker wrong--that it was "Keep Austin Wired" and referred to
an initiative to encourage the use of WiFi.
More recently, I saw this bumper sticker: "Keep Georgetown Normal."
Georgetown, for you out-of-towners, is the county seat of Williamson
County which is politically as red as Austin's Travis County is blue.
More recently still, I saw "Keep Round Rock Mildly Unusual." As you
might guess (unless you live here, in which case you'd know), Round
Rock is halfway between Austin and Georgetown.
No big surprise: Wikipedia has an article on the subject. From there I learned about these other slogans: "Keep Dallas Pretentious.", "Keep San Antonio Lame.", and "Keep Lubbock Flat."