INTERSPEECH 2011. Congratulations! In the past, the TSP Lab students used to use PowerPoint to create the posters - a bit of a kludge, and if the submitted paper was written using LaTeX, it might mean having to re-enter the equations (in addition to all the other annoyances of PowerPoint).
This pain can be avoided by doing the poster in LaTeX as well, as I did for my INTERSPEECH paper (see "Reconstructing Audio Signals from Modified Non-Coherent Hilbert Envelopes" on my research page). I used the a0poster package, and while it can be a bit daunting at first, with a good template it's quite easy to use. I've modified my own poster to be a small guide, with explanations: see inside the TSP Lab Template Package. It contains the a0poster class (probably an older version), and the McGill logo.