The Conservatives are organizing rallies for Saturday December 6th in cities across Canada. The locations are here: http://www.rallyforcanada.ca/
(Most of the locations are City Halls and other seats of government, but some of the locations are very partisan and others just seem completely out of touch. For instance in Edmonton the chosen location is NDP MP Linda Duncan's office. In Hamilton, the location is a large park far from dowtown.)
On the other side, the NDP has just sent supporters an email inviting them to attend "Conversation for Change" rallies across Canada on Thursday December 4th in the evening. No more specifics have been announced yet.
http://j-rad.ca/2008/12/conversations-for-change/
and apparently Labour groups are organizing a "Make Parliament Work" rally for December 4th at noon