NEW on the list. 

Podio is a web-based platform for organizing team communication, business processes and content in team workspaces. From Citrix.

Website: podio.com
Cost: Free and paid plans
Availability: Online

Top 100 Tools for Personal & Professional Learning 2018: –
Top 100 Tools for Workplace Learning 2018: –
Top 100 Tools for Education 2018: –

Past Overall Rankings
2017: –    2016: –    2015: –    2014: –    2013: –    2012: –    2011: –    2010: –    2009: –    2008: –    2007: –