jStackmenu is a jQuery plugin for creating a floating “stack menu”.
There is one but, however. The plugin only works on browsers that support CSS selectors, and falls back to a regular menu in case they’re not supported.
jStackmenu does have options, though: you can adjust the radius of the menu; change the menu’s direction; and adjust the time during which it shows.
It also has events–so you can do all the cutesy stuff you want with jStackmenu. ;)
Basically, the plugin should work well for, e.g. social media integration as in the picture, and maybe for a navigation in a portfolio.