If using Thunderbird to correspond with eBay customers, the Base.com plug-in will come in handy for you. Activation is fast and very simple. The plugin searches for related orders in Base.com basing on sender's e-mail address. This way besides the message content in Thunderbird you will see an additional panel, where you can immediately see given customer's orders. Order numbers are hyperlinked to take you directly to the order card in Base.com system with a single click. Instead of manually searching for a specific order, you will immediately see the order details.
eBay + Marketplace
eBay + Shops
eBay + Couriers
eBay + SMS applications
eBay + Other
eBay + hp erp_accounting
eBay + Fulfillment