Add Yahoo as a preferred source to see more of our stories on Google. Need some gifts for your kids, grandkids, nieces and nephews? More specifically, gifts they won't toss aside as soon as they open ...

Which invisible ink pens are best? Spies and conspirators have used invisible inks for millennia to send messages. In the modern age, invisible ink pens are an excellent way for grown-ups to ...

3:Write out invisible letters. 4:Light the letters with LED light on top and read your secrets. 5:Paper lacerating function. I won’t put a link because this is the jankiest think I’ve seen in a long ...

Remember those invisible ink pens? A new kind of ink made from algae lets you write or draw now, so someone can see your creation in stages. Freelancer Michael Franco writes about the serious and ...