Don't let your Scrum go stale.
At work, "No roadblocks" had become not just the answer to the third Scrum question, but almost a sort of punctuation to let the team know that the current pig is done speaking (useful, perhaps, for the team members participating via conference call). Maybe this is a good problem to have, no one having any roadblocks. But it could also be that your team isn't talking about the tough issues confronting it, especially if correlated with declining velocity or other indicators.
We ended up tweaking the questions a bit -- the third question is now something along the lines of "Do I need any help completing a task and/or am I available to help with the completion of another task?"
(It's still kind of fun to say "No roadblocks" at the end of a rant at lunch, and such. 8^))