The Individual Retirement Account (IRA) brings together two tremendously powerful forces, both of which benefit you: 1) compound interest, and 2) tax savings.
If you've got money that you can afford to invest for the long term, there's really no reason not to open an IRA. Lethargy is not a good reason. Inertia is not a good reason. Keeping your eyes wide shut about your future is not a good reason. Compound interest becomes even more powerful when it is not held back by the drag coefficient of taxes.
In those golden years, you want to be able to go out and buy the gold-plated golf clubs, jet out to Hawaii to circle the big island on a dolphin's back, savor the flavor of fine French food, make generous contributions to a cause that stirs your passions, or hire a trainer to help you get in shape for your Space Shuttle mission. You also want the opportunity to become your family's Most Beloved Ancestor -- the more you save, and the more you have at the end of the day, the more you're likely to have left over to spread around to your heirs. So you're really doing everyone a favor -- yourself included.