Examples:
1) Eduardo Moguillansky - limites
two trumpets being played at once, multiphonics of various overtone series flutter tonguing, natural tone/multiphonic glissando, valve glissando, valve vibrato, natural vibrato

2) Hans-Joachim Hespos - iOSCH - starting the note with an irregular glissando,"high, overblown dirty sound and simultaneous strike on metal", a barely perceptible pedal tone, offset a quarter-tone lower, rough microtonal fluctuating pedal tone, which also has slight multiphonic shadings, mixing vowel sounds with the back of the tongue closed, pedal range singing and playing at the same time, lots of air noise and yelling through the instrument and other special noises

3) Microtonal horn with quarter tone valve and extended 3rd valve slides - Samuel Stoll

4) Robin Hayward - Grave Mountain Diagram
Examples of many added vowel and consonant sounds, just intonation, half valves (scroll down for audio)

5) Christine Chapman of MusikFabrik talks about her horn with 2 bells

6) Exceptional brass players and extended techniques are well represented in other genres. Here's one example just for fun...