Recently while browsing online, I stumbled across this keyboard, a modified mishmash of mismatched letters emblazoned across the entire keyboard, all resembling a ransom note. While a ransom note style keyboard might not work for everyone, especially those of us who need to see where certain keys are, it's easy enough to upgrade your keyboard with fancy letters or typewriter text or images of LOLCats by following this Instructables tutorial.
We've espoused the keyboard makeovers before (using colored masking tape), but if you're looking for a little more customization, just find the font you prefer and print out the letters and numbers you care to replace in a size that will fit your keyboard keys (and on photo paper). Letters cut out of magazines and newspapers may work as well — it depends on what kind of paper stock you're working with. Here's a tip: you can easily pry off one of the keys, turn it over on a piece of paper and trace around it to get a template, then cut out the letters using that as a guide.
Next, grab some spray-on lacquer (quick drying is best), scissors and Isopropyl Alcohol. Carefully pry up and remove the keys you want to modify, cleaning the keys and keyboard as you go with the alcohol. It'll be helpful here to give each key a quick coat of paint in a color close to the background of your images, but it's not absolutely necessary. Next, start snipping out your pictures and attaching them to the appropriate keys, then give the keys a few quick applications of the lacquer and let dry. Snap each key back into its appropriate place on the keyboard — making sure each key is precisely where you want it to be — and you've just finished your very own custom keyboard.