I like to buy these adorable little critter-shaped paperclips from stationary accessories maker Midori of Japan on Amazon. They work just the same as regular paperclips, but they add a lot of sweetness and personality when the design matters, not just the function.
More than 24 designs are available in Midori's super-kawaii D-Clips series, with lots of little animals and birds to choose from: elephant, turtle, squirrels, whales, penguin, and more, on sale for $7-8 per pack of 30 clips at the time of this blog post.