I use Google Voice as a generic proxy for my public cell phone number to the actual land lines and cell phones that I use at customers, work, and in my private life. It’s great an has very few rough edges.
Unfortunately, it is pretty easy to get lingering Unread Messages so deep in your call Inbox that removing them becomes impossible. For several months, the Chrome Google Voice plugin looked like the following for me:
In the Google Voice inbox you can filter for these unread messages by using the following search syntax on the Google Voice web page
At this point you can clear them 10 at a time.