A plog is the contraction of project blog, usually for intranet communications.

A plog, defined by Amazon.com, is a personalized web log and can be updated by the authors of books previously purchased by the Amazon customer.

Plog is also a tool which allows users to update a blog using the wireless Palm OS.

pLog (note the capitalized L) was the name previously used for LifeType”s open source blogging software.

Additional information on plogs:
Amazon.com: What Is A Plog
The Virtues of Chit Chat
Plog for Palm OS
pLog changes name due to Amazon Copyright