Zen Cart contribution which would help you export easy your products into Yahoo Stores pay-per-click engine.

Some of the important benefits of listing in Yahoo Stores are:

Secure shopping cart & online credit card processing.
Advanced catalog and inventory management.
Intuitive sales reporting and business insight.
Easy access to participate in Yahoo! Shopping and Yahoo! Search Marketing.
Yahoo! Small Business has been an industry leader for more than 6 years
Yahoo enables thousands of businesses to sell their products and services online.
Yahoo! monitors their systems 24 hours a day, 365 days a year.
Yahoo's scalable, flexible system handles peak holiday traffic, and millions of dollars in sales volume.
Sell up to 50,000 items.
No per item fees!
Create and manage coupons and gift certificates.
Create valuable sales incentives such as percentage discounts, credits or even free shipping.