I usually have an old pair of 7x50s around my neck: these are very convenient for hand-held use and their wide field-of-view is good for locating faint targets prior to aiming larger instruments at them.
I also use a pair of 15x70s for observing clusters and comets, but these need to be supported on a tripod somehow.
They are the smaller pair in the background in this picture: viewtopic.php?f=6&t=23
whereas the pair in the foreground are 25x100s which give great views but need a very substantial mount!
Probably the best binoculars for hand-held use are the image-stabilised
types, but these are very expensive.
Regarding the "sky-mirror", BAS member Peter Miskw made himself a DIY one (there is a picture of it somewhere in the Forum but I can't find it at the moment) using a pair of ordinary glass-fronted mirrors, but it's better to use a single front-surface
mirror. This method of observing is very comfortable, but as the mirror faces up to the sky it will cool quickly, so you'll need a strategy to stop it dewing up - either an electrical heater under it or a fan blowing across it.
Here are a couple of links showing home-built mirror-mounts:
http://www.swindonstargazers.com/notice ... oard03.htm
http://www.craigcolvin.com/astronomy/bi ... irror.html
and one example of a supplier of front-surface mirrors (found by putting "front surface mirror uk" into a search-engine):
http://www.scientificmirrors.co.uk/Auto ... rrors.html