Can anyone pls explain what and Id90 is? I think it is a 90% discount for a non-confimed seat. For FEDEX, for example, does family have ID90 benefits? How about parents? Do only some pax airlines accept these? Thanks.
FedEx has agreements with numerous airlines that provide ID-90/ID-50, etc. I believe they are available for family members as well. Often, though, they are not great deals because it is a 90% discount off the full coach fare, i.e. the "walk-up" fare which can be pretty darn expensive. Also it's still a standby ticket. SouthWest has a good deal that seems to get used more often. They charge $35/ticket for a standby ticket. I've had good luck with those with my family. There's a publication you can get (I got mine the first week of orientation at Fedex) that lists all the good deals available for employees (and there are a bunch).
ID90 tickets tend to particularly beneficial for overseas travel. For example, I flew my family to Rome on my carrier. Then I used ID90 tickets on Air Malta and flew my family of four to Malta for about $120 total, round trip. I have friends who've flown to places such as Tahiti or Indonesia for similar cheap prices.
Be aware, however, that ID90 tickets usually must be purchased from your own airline's ticket counter or employee travel office -- not directly from the airline on which you intend to travel. So, you have to get them before you start your trip.
Every airline has certain agreements with certain other airlines around the world. Some airlines print a list of their reciprocal agreements. At other airlines, you may have do do some digging -- usually by asking an agent to check in the reservation system.
In any case, ID90 can be a great deal in certain situations.
ID-90's and ID-75's vary from carrier to carrier as to who is allowed to use what. You need to check with your pass bureau or interline office to see what the stipulations are regarding interline travel. I agree that a lot of times you can get an E-Saver for cheaper and it's positive space.