I don't know much about Potter 'verse, but as to the historical kind:
While I do not care to go into great detail here (email me for more info), hands of glory are (WERE, I mean WERE) often used as candle holders. Among their powers, they keep everyone in the house asleep, so who can see their light seems rather a moot point. However, I think I remember a recipe for a candle whose light only the holder can see in the Greek Magical Papyri, so try looking there.
As I recall (book not handy now), _Ritual Magic_ by E. M. Butler has some good info, as does (book handy and quoted below) _Occultism, It's Theory and Practice_ by Sirdar Ikbal Ali Shah (one of my favorites. my copy has no printing date info, but appears to be from around 1920ish)
"The famous Hand of Glory which was supposed to render the owner invisible, as well as put all members of the household hE wished to rob into a heavy slumber, is a great favorite among the grimoires. (footnote: An interesting link with this belief can be found in Indonesia: where a thief collects dust from a grave and throws it round thehouse of his victim to make the household sleep.) ... [directions for manufacture from the _Little Albert_ grimoire] ... [an antidote (really more of a ward)] ... [the story related before about the maid putting the flame out with milk] [another story of its use]..." There is about 3 pages of info; I got tired of typing. The book then wanders off onto other invisibility experiments.
As I understand it, the tallow the candle is made of is mostly made of the fat of the hanged man, beeswax, and sesame oil (not unbaptised babes; think how many babies you'd need to make five candles!)
Hope that helps. I can try to scan out the pages if you need them, but it's a delicate book, so I might not be able to manage it. Email me if you want more info.
On a vaguely related (slightly late-steampunky) note, Mercury dimes (1916-1946 US 10 cent coins. They have a picture of winged Liberty on them) are often used in modern invisibility workings. They are the most beautiful coin ever. Mercury is (according to Edith Hamilton) the god of "mathematicians, theives, and other ne'er do wells".
http://en.wikipedia.org/wiki/Image:Mercury_dime.jpgPS-PLEASE tell me why you want to know. PLEASE.
