There's not a lot of talking on the flight deck of an aircraft carrier. Yelling, yes. Talking, no. It's so noisy, everyone wears military-grade hearing protection.
If you work in a similar acoustic environment--maybe on a factory floor, at construction sites, or in the stands at rock concerts--you might want to check out the Sensear SP1, which protects your hearing by blocking out damaging noise while allowing speech through.
The rig consists of noise-blocking earpieces with embedded microphones for picking up outside sound.
The SP1 doesn't actively cancel sound. In fact it is designed to make sure the wearer can hear alarm bells and other danger noises, like approaching airplane engines. The electronics in the device serve the purpose of picking speech out of horrendous background noise and amplifying it for the listener.
It is, in other words, much like a hearing aid, except designed for ultra-loud environments and with no concession to style or size: the control unit is a safety-orange box you wear around your neck.
The SP1 (about $300) has a microphone for connecting to two-way radios. The SP1x model also has Bluetooth so it can work with mobile phones. You can plug your MP3 player into either.