The Source Canada has a great deal on right now until 15th August 2012. Save 50% on 2 of their Logitech wireless mice.
Right now you can get your choice of Logitech M325 wireless mouse that was $39.99 for just $19.99. You can get a version in blue for a more neutral look or you can go with my favorite in pink. Both are on sale for this price. Both mice include the 1 AA battery needed to run it. I like that you can actually turn the mouse off with a switch on the bottom because you will extend the battery life for a long time of you do this every time you are done using it.
We have 2 computers and both of them have a wireless mouse. Since having the convenience of a wireless mouse, I would never go back to one with a cord. I wanted to do some price comparisons and I found the same mouse in violet at Best Buy for $34.99. I also found it at Staples Canada for $34.93 in all colors. For the M325 version (which is a good one), the deal at The Source was the best I could find.
(Expiry: 15th August 2012)