ERP (SAP, Oracle, JD Edwards, PeopleSoft, BAAN, QAD, Lawson)
CRM including Siebel, salesforce.com, Clarify, Remedy
All major databases including Oracle, DB2, SQL Server, Sybase, Informix
Flat-files using FTP, HTTP(S), e-mail
XML and Web Services
EDI
Middleware and all major EAI platforms
Project management applications including CAs Clarity
And many more...