I'd like to nominate the dbag CAP flight pilot operating around DTW this morning who acknowledged all clearances with just a "will do..." and no call sign.
DTW Dep: CAP Flight 123, climb and maintain 7000, fly heading 150.
CAP Flt 123: Will do...
DTW Dep: CAP flight 123 proceed direct XYZ, climb and maintain 9000.
CAP Flight 123: Will do...
DTW Dep: CAP flight 123 contact Cleveland on 124.5.
CAP Flight 123: Will do...
I know wearing a military flight suit while flying a 172 or a C90 King Air makes you cooler than cool but c'mon man...that's really unprofessional.