alt.stagecraft
     The original stagecraft newsgroup. This was supposed to be replaced
     by rec.arts.theatre.stagecraft but like many alt.* newsgroups it
     refused to die. alt.stagecraft is lower traffic than r.a.t.s..
     There are often interesting threads on alt.stagecraft that don't
     get crossposted to r.a.t.stagecraft, so it's well worth reading
     both
rec.arts.theatre.stagecraft
     The 'official' stagecraft newsgroup. Lots of noise, but lots of
     signal too. Discussions are mostly about set, props, lighting and
     sound but any backstage topics are welcome.
net.theatre.stagecraft
     The Usenet2 stagecraft newsgroup. Pretty much the same charter and
     content as rec.arts.theatre.stagecraft but as part of Usenet2 it
     should be nearly free of spam. See
     http://www.blighty.com/nettheatre/ for information on how to get
     access to it and some posting rules
rec.audio.pro
     A lot of good stuff here. Most people are discussing studio
     recording rather than sound reinforcement, but there's a lot of
     overlap. At the moment it's swamped with 'for sale' ads (so it's a
     good place to find second-hand equipment....) but it will hopefully
     split, adding a .marketplace subgroup sometime soon.
sci.engr.lighting
     Primarily for architectural lighting professionals, but you can
     occasionally pick up some really good ideas.
alt.pyrotechnics
     Just one word. Don't. Look at rec.pyrotechnics instead.
rec.pyrotechnics
     There are a lot of very knowledgable readers lurking here, and a
     lot of useful information, particularly about making your own pyro
     (and why you shouldn't). Most of the Kewl Bomz crowd get squashed
     fairly rapidly.
rec.org.sca
     I'm not even going to start trying to describe the Society for
     Creative Anachronism, I'll just say they're a nice bunch of unusual
     people and as a group they probably know more about historic and
     pseudo-historic costuming than anyone else. If you're a costumier
     or you do props it's well worth lurking here, if only to grab ideas
     and commercial contact info. (Also, if you need good, really good,
     historical costumes and are prepared to pay for them, some SCA
     members do commercial work.) rec.org.sca is a group with it's own
     rules, more so than many. If you're not an SCA member yourself you
     should lurk for a while before even thinking about posting a polite
     inquiry.
rec.crafts.textiles.sewing
     Lots of general sewing stuff - worth a look for a costumier
rec.woodworking
     Well... It's about woodworking and woodworking tools. It may be of
     interest to the occasional setbuilder.
comp.cad.autocad and comp.cad.microstation
     If you use one of the big two CAD tools these groups are a great
     support resource.
sci.electronics.*
     Electronics design and finding odd components
rec.arts.dance
     There are occasional relevant threads, but it's a very high traffic
     group with very little of interest to designers, or even
     choreographers.