Handily, it’s fairly easy to customise, as I found when Bambuser wasn’t among the options listed, and it also picks up widgets I’ve made on various sites and gives me the option to include them if I wish.
I’ve added it as a permanent badge on my blog, but I can embed it on any of my sites if I want. Oh, and you can pay for an upgraded service too, but I’m quite happy with this one.
Of course, I could have mashed my Friendfeed rss into a widget and come up with something a bit like this, but it wouldn’t have looked as nice I suspect. And, thanks to Retaggr, I haven’t had to.