Prue has the power to move objects with her hands.  She used to channel her powers through her eyes but her power grew.  She is very strong and can move almost anything (that isn't to heavy).

In the episode "Love Hurts", Prue and Phoebe accidentally switched powers.  So for a limited time Prue had premonitions.  Prue then told Phoebe that she would never tell her she had no vision again.

Piper has the power to freeze time with her hands.  Her power is very useful because whenever she doesn't feel like talking to someone (like the jerk chef at Quake).  She just freezes them.

When Piper first got her power she couldn't control it very well. Now she can "stop" time whenever she wants and "restart" time whenever she wants (or whenever she needs to).

When Leo was hurt Piper switched powers with him.  She had the power to heal and to find a person if she listened for them.  It took her almost a whole episode to figure out that the trigger was love. (She told Leo that she loved him).

Phoebe has the power to see the past and the future (premonitions).  In the beginning of the season she could only see the future, but now she sees the past to. She can see it by touching an object that has a enough "psychic" energy on it.

For a short while Phoebe had Prue's power.  She later said that she liked her power much better.  The only way Phoebe could use Prue's power was to be angry. So Prue had to "push her buttons" to make her angry.