Interesting behavior from the Twenty Eleven Ephemera widget.
The funny thing is that it won’t show up at all if you have no recent Aside, Status, Quote or Link posts but if you do have even one of the above posts it will show up in the proper place where you placed it on your sidebar. That’s not so bizarre; in fact I would call that good behavior. The interesting part is that it will be the only widget that will show up on your Showcase page, on the left sidebar and with the title of Ephemera instead of the title you gave it.
Correction: I learned when I deleted the widget from my sidebar and it did not disappear from my showcase page that the Showcase Page Template has it’s own Ephemera widget built in with it’s own settings. It just happened to show up at the same time as the regular sidebar Ephemera widget because I created the first Aside post that made both Widgets appear for the first time.