(Working in IT) I love laptop stickers for this. Whenever I'm returning from a conference a quick look around the lounge will reveal plenty of people with laptop stickers that are an easy to to startup a conversation. "Oh you're into $LANG/$TOOL, did you go to $CONF too?".

Laptop stickers are a perfect means to signal who you want to talk to, and who you don't, without saying anything.

Ah man. Probably should have considered that before slapping a “Nuke the Whales” sticker on the back of my screen.

so i put on the star trek sticker but not the star wars sticker. got it. thanks.

And in the end, it feels good and fresh. Just like any other (meaningful) skill, decent social skills put forth significant effects on one's awareness of their local surroundings, and with good social skills, invaluable experiences. I've struggled with it for the best half of my life, and later ignored the need to take action and improve. I moved on to finding out the subtle beauty of just pulling up a conversation with a completely new person, of course our perspectives and opinions might differ, and that's where I see the beauty and without it, the world wouldn't have been so dynamic so I think.