Hi Trad
If you do a search for Laddermat, I think theres a vid or it on youtube , stops ladder slipping. From a going up heights point of view its all psycological. I dont spend much time up ladders but I do spend quite a bit of time rock climbing and for me I know if I can do a route and Ive done everything safely then being 100 foot up is no different to standing on the flat being 100 foot away from something!
In 20 years going up a ladder youve never had a fall? Why start now? Im guessing the lay off has you spooked, knocked your confidence, why not clean your own windows on the ladder, get up there with your missus hanging out the window if you have too, have a brew, and stand at the top for as long as it takes for your brain to get back to the stage where you think about the height differently. Climbers do the same thing, even climbing up and dropping off on purpose - Ive done it the first few falls you fill your pants but after a while it becomes almost fun. Also concentrating on what you are doing ie the cleaning will take your mind off the height, hope this helps good luck. PS if youre anywhere near sheffield Ill come and work for you!