Weird light bulb

That's just how it was labeled... Weird Light Bulb. I've been collecting bulbs on and off for a while, but I never saw one like this. As you can see, it works, and it has a nice glow to it. It has a normal size base, but the bulb is small, (3 1/4 tall over all, 1 3/4 wide), about like an appliance bulb. I see no markings of any kind, and it doesn't seem to get hot when on. If anyone knows what this bulb was for, please let me know!