The last frontier for marketing has always been the public washroom, but even our privacy there has gone the way of "Sandra Bullock, trusting wife."

Sometime ago, the most confidential place we had became subject to framed, bathroom stall ads. Next came posters above toilets and TVs on the walls. And then (FYI, ladies), there arrived branded urinal cakes. It's not enough to pee in your own solitude – men must now do it all over Gene Simmons.

Of course, you didn't think the ad men would stop there, did you?

According to the Toronto Star, a Canadian firm is now bringing advertisements to bathroom mirrors across the country, marking a complete and total marketing invasion of our loos and WCs. AddMirror Canada Ltd. has taken to branding mirror space inside restrooms in Toronto, Montreal and Vancouver, and will install similar reflective billboards in Calgary bathrooms next month, the Star reports.

For such a simple idea, the mirror ads are actually quite complex. They're printed on film behind two-way glass, and the marketer's message is illuminated by LED backlighting. Most ads run on a 20-second loop and can encompass the entire mirror face.

Any silver lining to these ads – and believe me, they appear few and far between – is that the Canadian mirror ads have been improved from their original U.K. counterparts to be more eco-friendly. The ads will work on motion sensors so they're not blaring bright, neon messages when no one's even in the can.

Now, while no one should be surprised by the move to keep cramming ad space into a washroom, will seeing a company's logo or ad on a bathroom mirror make us really want to buy their product? Chances are, bathroom-goers will experience one of three reactions when they see ads muddling up their reflection in the mirror: intrigue, indifference or wrath.

When your local watering hole undoubtedly moves to put ads on its mirrors, which response will be yours?