Before I argued that slightly irritating the audience's senses could support your presentation. Two cases of overdoing it:
More details about these ads on Ads of the World: Nycomed and Eurostar. I recommend adding this blog to your RSS reader.

Click "view post" to read the full blog entry. If you liked this post, why not subscribe to daily updates about presentation design via email? Just blog posts, no spam. You can find Jan Schultink on Twitter here.