From FlyerGuide Wiki

JetBlue offers free wireless at Long Beach (LGB) and New York-Kennedy (JFK) airports.

Airports served by JetBlue with free wireless for all airlines are...

AUA Aruba (Netherlands Antilles)
BTV Burlington (VT)
CLT Charlotte (NC)
CMH Columbus (OH)
FLL Fort Lauderdale (FL)
RSW Fort Myers (FL)
JAX Jacksonville (FL)
LAS Las Vegas (NV)
NAS Nassau (Bahamas)
ONT Ontario (CA)
MCO Orlando (FL)
PHX Phoenix (AZ)
PIT Pittsburgh (PA)
PDX Portland (OR)
RIC Richmond (VA)
ROC Rochester (NY)
SRQ Sarasota (FL)
SYR Syracuse (NY)
TPA Tampa (FL)
TUS Tucson (AZ)
PBI West Palm Beach (FL)