Aha - Aha! is the new way to create visual product roadmaps. Web-based product management tools and roadmapping software for agile product managers.
Intercom on Product Management - The ultimate resource for aspiring product managers
ProductPlan - Cloud-based product roadmap software solution
The Product Management guide - A book on how to create and ship products that people love
sharpcloud - SharpCloud is visual communication software for the Enterprise
Software Product Management Stack - Resources & tools to help you manage your software product