Last week, we asked Rate the Adsters to consider a video riddle from Samsung on YouTube. London-based The Viral Factory posted a video that asks YouTube viewers how filmmakers make a camera phone disappear without edits or effects. When it comes to unmasking magic, it turns out most of you spotted the ruse. (Spoiler Alert: When the man stands in front of what looks like a mirror and swipes his hand in front of the phone, he's actually not in front of a mirror, but another man mimicking his actions.) And when it comes to the creative, there was resounding applause for the tactic and execution.

Echoing Rate the Ad's genuine whodunit excitement, commenter "ltjohnson" says, "I like this because it's transparent about being a challenge from Samsung. It doesn't pretend to be a grassroots phenomenon. It's a genuinely interesting riddle. And the medium fits the message brilliantly, especially now that YouTube has HD videos."

This week, we'll stay with YouTube and turn to short films from Google for its web browser Chrome. Yep, you heard right, the search god is indeed turning to uncharacteristic marketing tactics, in this case a web video campaign, to push the browser, which has only gained measly market share from competitors Internet Explorer, Mozilla and Safari, since its launch last fall. Today, Google launched a YouTube channel with 11 videos extolling the virtues of the new browser from designers, illustrators and creative shops such as Motion Theory and Superfad—Ad Age has more on the story. This effort follows Chrome Experiments, a website featuring user-submitted coding experiments. While the films are only on YouTube for now and Google's hoping for viral pass-along, a media buy is not out of the question. Can you believe it? Is Google diluting its too-cool-for-advertising image to save Chrome? Is "advertising for Google" an oxymoron? Will we be seeing Google spots on TV anytime soon? Share your thoughts on the films and Chrome marketing, below.