For new Zipcar members in New York City and New Jersey, buy a 1-year membership for $50 and snag a $75 driving credit for free via coupon code "NYC75". That's the best such offer we've seen from Zipcar since last summer. Note that the $75 credit must be used within 30 days of joining and a one-time $25 application fee applies. Coupon ends August 10.
Alternatively, today only at Groupon.com, new Zipcar members receive a 1-year membership and two $25 driving credits for $50. Although this is $25 less in free credit than the above deal, it includes the cost of the application fee. Plus, the two credits come in separate installments, each with an individual 30-day expiration period.