We stayed far too much time without mentioning that old-time favorite, Springheel Jack.
Since I am lazy this is a nice and brief chronology of his activities I've found on the Internet.
There are a few very interesting facts about this strange phenomenon.
One happened on the 23rd February 1838, when Springheel Jack knocked at the door of a house on Turner Street, Londo and asked for the homeowner, a Mr Ashworth, calling him by name. The servant who opened the door was comprensibly scared to death and his screams drove away the curious creature. A few days before a young woman returning home had noticed Jack standing at a street corner, like he was waiting for someone. The question is obvious: why? A prankster would not risk his own life by walking around in such an attire when lynch mobs roamed the streets ready to club to death anything remotely unfriendly.
Another interesting thing is the hiatus between its various periods of activity: 1837-1839, then 1843, 1845 (read on though), 1877-1879, 1904, 1920 and finally 2005.
The 1845 episode is particulary curious because it happened in New York, USA, and was the only one during which Jack actually killed a person. Given the fact that he was usually very aggressive but never seriously hurted anybody I am inclined to treat the case with caution.
Henry, Marquis of Waterford, was long held as a suspect but this may due to his "shady" reputation since he was killed by a fall from horse in 1859 (of course he could have named an heir...) and the fact that nobody ever managed to replicate Jack's astounding athletic feats by any mean. The German Luftwaffe briefly experimented with a system of springs (like the one the Marquis was rumoured to use) for her Fallschirmjager (paratroopers) but this resulted in some catastrophic results for the poor volunteers and was quickly consigned to the scrap heap.
What are your opinions on the matter?

One thing that comes to mind immediately is the similarities with mothman/ owlman reports. Curious that stories from different continents should have key elements in common.

Vallee mentioned this possibility in Dimensions.
Some researchers ruled out Springheel Jack as mass allucination or a piece of urban folklore but I tend to be careful on this point. First fact, it is well known that Arthur Wellesley, the Duke of Wellington, took more than a passing interest into it. The Iron Duke was well known for not being given to flights of fancy. Second fact, another quite similar case popped up in 1944 in the US, involving an entity quite similar to Jack known as the Mad Gasser of Mattoon. As Jack the entity was wearing a flowing cape and a close fitting suit and as Jack he used some kind of "gas" to attack his victims. Again, the entity seemed more interested into causing panic and confusion than seriously hurting anybody.
The town of Mattoon, Illinois, was quite different in 1944 from early XIX century London. It was the classic place where "nothing happens", everybody knew each other and most of male population was away, serving in the military. Local police officers grew quickly tired of the story and put the blame on gases used in the local diesel engine factory. Trouble is most of locals, men and women, worked at the factory and were familiar with the smells.
A prankster would have been quickly identified and caught (or lynched).
There's also a very little known yet strikingly similar case from rural Virginia in 1933 which was unearthed by the usually reliable Troy Taylor.

I seem to recall Jack killing a prostitute at Jacob's Island by hurling her off a bridge and into Folly Ditch, where she drowned. There is also a similar case regarding ringing doorbells, only he was greeted at the door by a girl called Jane Alsop- where he spewed "a quantity of blue and white flame from his mouth, and his eyes resembled red balls of fire" (the Times, possibly 22nd Feb, 1838) into her face and subsequently began attacking her with fingers that supposedly resembled metal talons.

It appears in a book called The Unexplained by Karl Shuker. It's a great book, if you can find it: Mine is very worn and very used.

You might find my webpage on Springy interesting

http://www.blackcatpress.co.uk/Spring_Heeled_Jack_Page.htm

I seem to recall something in a recent (possibly the most recent) edition of Fortean Times re-evaluating the evidence for SHJ. From memory (the FTs are on a shelf next door and I'm on the couch and far too far away), it indicated that a lot of it may have been media hype, and noted the huge date differences between sightings, and an earlier case. It also covered the lesser known sightings, such as those in Liverpool!

What an incredible story - I'd never heard it before. Thanks for all of the links. I do wonder how much of the jumping can be attributed to darkness, terror, excitement, etc.