Amazon first introduced its line of "Alexa Gadgets", which are devices meant to enhance Echo devices in "fun and playful" ways, with the $20 Echo Button last year but, since then, there hasn't been much movement on other Alexa Gadgets.
That has now changed with the Alexa Gadgets Toolkit beta that will give tools to developers to create their own Echo-connected accessories. The Alexa Gadgets Toolkit gives developers APIs and technical documentation for building devices that can interact with Echo speakers, as well as helping with things like pairing and connectivity as well as software updates between your gadgets and their paired Echo devices.
To be clear: these aren't more devices that necessarily feature the onboard Alexa assistant. Rather, they would pair up with to work with an Alexa device. Amazon has a variety of examples of the sort of gadgets that developers can create, to get an idea of what's possible: things like a outdoor gong that chimes when a backyard playtime timer has concluded, a flag that pops up when your Echo gets a notification, a cuckoo clock that pops its head out whenever you say "Alexa," or a singing fish that can dance along with a song from Amazon Music.
Amazon has a variety of major developer partners on board to use the Alexa Gadget toolbox, too, including Hasbro, WowWee, Baby Plus, and eKids. According to the company, the first products that use the Alexa Gadgets Toolkit will be out later this year, starting with dancing plush dolls and (of course) perhaps an updated Furlexa.