KJZZ-FM 91.5: Was once a non-commercial jazz music station and called itself K-Jazz. Has been mostly NPR news and talk for 15 years or so, but still plays about 8 hours of jazz each night.
It was cut back to 5 hours (8 PM - 1 AM) since, like many other NPR stations, it fell in love with the BBC.
KTAR-AM 620: Legendary call letters associated with the frequency since the 1920s, and with news/talk for more than 30 years. Now branding itself as "Arizona Sports 620".
And originally stood for "Keep Taking (the) Arizona Republic," or "K-The Arizona Republic" (or maybe both) after the now-Gannett/KPNX-owned fishwrap bought it in 1929. The Republic found out that its original choice for call letters, KREP, was confused for "something else," and changed the callsign a few months later. The paper sold KTAR in 1946.
KMVP-AM 860: Call letters meant to evoke "Most Valuable Player" as a sports station. Has been Gospel for a couple of years.
It still has its finger in the sports pie, acting as the overflow station for ASU when KTAR airs a Suns game.
Others from Phoenix's past (in no particular order):
KRDS 1190 "Cards Country" - 1960s & '70s, well before the arrival of the football team.
KGME 1360/550 "The Game." Still has the KGME call letters, but has been branded as "XTRA Sports 910" since moving to that frequency in 2000.
Speaking of 910, when it was country-music KJJJ in the '70s and '80s, it branded itself as "KJ-910."
KUPD 1060 "Cupid" when it was an early soft-rock station. Now sports-blabber KDUS.
KSTM 107.1 "The Storm" as an album-rocker in the '80s.
KMEO 740/96.9 "Cameo" when it was an elevator music station in the '60s & '70s.
KFCB, the first station in Phoenix, branded itself with the slogan "Kind Friends Come Back" in the 1920s. It became KOY in 1929.
KEDJ 106.3 "The Edge" in the '90s. This alternative rock station was licensed to the hard-core, edgy town of Sun City.
Now Spanish-language KOMR.