Examples:
(1) uncompensated blood donation
(2) volunteering
(3) operating a soup kitchen
(4) disaster relief
Several types of altruism and any act is rarely "pure".
Motives may involve of the following (after Evans and Ferguson):
(1) "pure" from compassion with getting absolutely nothing in return
(2) having been taught that it is the right thing to do, out of a sense of duty
(3) "warm glow" with positive self-image
(4) impure or mixed (combination of "pure" and "warm glow")
(5) reluctant (doing something because someone has to do it and no one has stepped forward)
(6) hedonistic (hoping to get something in return)
(7) manipulative (having a reputation for helping others may result in others being willing to help the actor)
(8) kin or parochial (preferential helping of family or group members)
(9) atonement for havng done something wrong
Whatever the motive a person on the receiving end of an altruistic act is often extremely grateful.
