These little LEDs are more than just brick-ish. They are perfectly compatible with Lego! So take that Lego vehicle and add some working headlights or make your robot’s baby blues really shine!
Each LED is precisely the same size as a Lego 1 x 1 brick. The top of the blocks are also stackable. (The bottoms have those pesky LED leads on them though, so you’ll need to factor that in to your design.)
Sparkfun’s 10 pack kit includes 2 of each color: red, yellow, green, blue, and white. You can buy a kit online for $9.95.