While any benefits an employee receives from their company is personal, it is known that airline employees get airline perks that you're most likely not going to get flying a desk at your local office building. Generally specific limitations are kept within the company, but free stand-by travel, discounted revenue travel, negotiated interline agreements, and other 'travel' discounts/perks are common.
When I worked under DL we had unlimited free stand-by domestic travel, 6 free stand-by transoceanic days per year (traveler pays taxes), unlimited yield fare transoceanic travel (after the 6 free ones were gone), and access to ID90 tickets (stand-by travel for 90% off lowest published fare) on dozens of airlines, and ID95 tickets (stand-by travel for 95% off lowest published fare) on SkyTeam airlines. That with a multitude of car rental and hotel chain discounts for when you got to where you were going. Our flight benefits included your parents, significant other/spouse and dependent children, plus 8 buddy passes for friends and other family per year. We had to pay $50/year to have a flight pass card.
There were quite a few other things as well, but most people only care about the flight benefits. I wouldn't expect an active airline employee to just offer up their benefit package to a public forum, but you can expect it to include a mix of discounted and free air travel within the company, and more often than not, interline agreements as well. How much you get to use them varies within companies quite a bit. DL counted transoceanic as 'days' and everything else as a trip, whereas UA and some other carriers permit employees to X number of segments.
