QZ Tray - Print raw (ZPL, ESC/P, FGL), HTML, PDF as well as communicate with USB, HID, and serial devices...
Printer Pro - Print attachments, receipts, documents, web pages from your iPad and iPhone.
CalPrint - CalPrint uses your existing reminders and calendar entries on your iPad or iPhone (Exchange, iCal and Google Calendars etc.
PrintNode - PrintNode offers cloud printing solutions for web applications.
Air Sharing - Air Sharing lets you bring your documents with you — without bringing your computer.
Printix - Printix is a cloud-based print management platform.