Croyde from the air (Kite aerial photos)

[Fab Foodie]

Ahhh memories... Is the surf-club still there?  I think my membership's expired though... 

[andygates]

A line climber doesn't use batteries. It uses a sail to let the wind push it up the line

Kinky!  You'd need a fair sail to pull up a dSLR though, no?

[clarion]

I've seen hefty equipment, inc medium format, lifted with a reasonably-sized device.  Worth doing the sums.

[andygates]

But you'd still have a sail directly attached, which might be too noisy for regular use.  For an ascending video, awesome.  But attaching the rig to the line as you go up isn't hard.

[frankly frankie]

The powershot has a scripting language - you can make it snap away every ten seconds or whatever.  Perfect for this sort of thing!

A night shoot might be challenging.  Guy Fawkes would demonstrate the superiority of your system over a mere intervalometer (until the kite goes down in flames).
(and IR releases have a pathetic range best measured in inches, in my experience)