BuyMap

BuyMap lets you search eBay by UPC, barcode, ISBN, EAN, or keyword and view all matching listings in one place. It provides product research, price comparisons, and shipping estimates to help resellers, collectors, and shoppers make smarter buying decisions, with listing filtering, full descriptions, and a Chrome extension for quick matches.

🔗 Full discussion: https://www.reddit.com/r/InternetIsBeautiful/comments/1rc012h/i_made_a_web_app_that_lets_you_see_all_matching/