The VP has another important power: he gets to break ties in the Senate (which are not that uncommon, the 100 seats often being split roughly evenly between the two major US parties). Al Gore has used this power on a couple of occasions to help the passage of bills that otherwise might have gone down to defeat. The prime example of this is the Omnibus Budget Reconciliation Act of 1993 (OBRA 93), which added the new 36% and 39.6% tax brackets but did not include the child tax credit promised in the 1992 Presidential campaign. The bill passed the House and was stuck 50-50 in the Senate, at which point Gore voted for it, and Bill Clinton signed it into law.

This is a VERY important power. Whatever your opinion of OBRA 93 (and opinions vary--widely), there's no doubt that it would not have passed in its then-current form without a little Vice-Presidential nudge.