@myleshorton has been showing the widget around, and he's received two pieces of feedback that we should examine:

First:

if there's any way to provide a tiny bit more technical reassurance that it's totally private and non-invasive. Somehow double down on the insurance that those who participate are not exposing themselves somehow. As it reads it's a tiny bit "don't worry, it's totally safe--trust us!" Maybe even a link to "more details about how we guarantee your digital privacy while you serve as a bridge to victims of censorship" (but not that wording) and then get into a tiny bit of technical reassurance when the user clicks through.

Second:

[@noahlevenson paraphrasing here]: The call to action is a bit ambiguous, and an otherwise savvy user missed the "on" switch at their first glance.