make 90V DC and 1.5V DC for 7-pin valves used in old radios
http://www.vintage-radio.com/projects/battery-set-psu.shtml
http://www.web-ee.com/Electronic-Projects/projects/eprom_psu/index.shtml
gives +/-15V outputs and takes power from external AC power supply
http://sound.westhost.com/project05.htm
http://www.rlocman.com.ru/am/a01004.htm
http://www.recherche.enac.fr/~puechmor/e_rectif/e_rectif.html
This article has table of some power consumption values (in watts) for common items in a personal computer.
http://www.howstuffworks.com/power-supply3.htm
a practical improvement guide
http://www.e-insite.net/ednmag/archives/1997/030397/05DF_06.htm
http://www.musicfromouterspace.com/analogsynth/powersupply.html
outputs regulated +-15V
http://www.renkus-heinz.com/Schematics/CONTROLERS/POWER_SUPPLY_X12-X14-X24.pdf
This regulated power supply can be adjusted from 3 to 25 volts and is current limited to 2 amps as shown, but may be increased to 3 amps or more by selecting a smaller current sense resistor (0.3 ohm). The 2N3055 and 2N3053 transistors should be mounted on suitable heat sinks and the current sense resistor should be rated at 3 watts or more.
http://ourworld.compuserve.com/homepages/Bill_Bowden/page4.htm#ps3.gif