From a Tegan and Sara MySpace Bulletin:

A special FREE! ALL AGES!! acoustic performance and instore appearance is happening on Thursday night at Criminal Records in Downtown Toronto.

Thursday, October 4th
11pm
Criminal Records
493 Queen Street West (near Spadina)

The store will close at its regular time of 8pm, and will not re-open until shortly before the performance at 11pm, so if you come early expect to be lining up outside! There is limited space inside the store, so admittance is on a first come, first served basis.