This is the Wi-Fi Detecting T-Shirt, which would have been really handy on my recent trip to Belgium, where I constantly got my laptop out, searched for hot spots to no avail, put the computer way and repeated the same process ten minutes later.
I love its little blue bars is framed in the screen of a white MacBook. I also love how they've managed to get so much out of a piece of fabric you can drape over yourself. It's a brilliant shirt! It's also great because it can detect speeds of 802.11 b/g (which is what my laptop is on), so whenever my chest starts to glow bright blue, I know that I can watch some crap Renetto's waffling about on YouTube.
If you would like the shirt, go here to Firebox UK and get your own super-duper wowzer bowzer Wi-Fi Detecting T-Shirt (but don't make them go out of stock, I want one too!).