For a little splash of retro colour in your stationery drawer, check out these Tetris-inspired sticky notes! Not only are they clever and delightfully nerdy (Sheldon Cooper from Big Bang Theory would love these in his Christmas stocking), but they’re downright handy – especially if you need to make notes that require more than a few colours of stickies.

Plus they’re an amusing way to pass the time when you have those pesky cold-call salespeople on the phone. Sigh.