Aha - Aha! is the new way to create visual product roadmaps. Web-based product management tools and roadmapping software for agile product managers.
Software Product Management Stack - Resources & tools to help you manage your software product
TargetProcess - Agile Project Management Web Application
The Product Management guide - A book on how to create and ship products that people love
ProductPlan - Cloud-based product roadmap software solution
Product Management Exercises - A repository of product manager job interview exercises