This page presents a potpourri of possibilities for expanding one's sound which, for the most part, I haven't pursued myself. These include percussion, extended guitar, and the Roland VG-8, which is in a class by itself.
There are also some miscellaneous links, which may not be strictly relevant to playing as a one-person band, but which I found interesting and useful.
Ever since the thirteenth century, a one-man pipe and drum ensemble called pipe and tabor (pronounced "tabber" by purists) had been in use, first in northern Spain and southern France, and spreading in the next century until by the Renaissance it covered most of Europe: a sort of layman's precursor of the fife and drum combinations. -- Sibyl Marcuse, A Survey of Musical Instruments, Harper & Row, 1975
An absolute must read for anyone interested in this combination is THE PIPE AND TABOR, "An Address to a Society of Morris Dancers, Oxford, February 12, 1914," by Sir Francis Darwin, son of Sir Charles Darwin.
I've seen several people play hi-hat cymbals along with guitar, and tried it briefly myself. It was easy, and sounded good. But it was impractical for my setup, given the other tasks already assigned to my feet.
In several music catalogs, I've seen a combination guitar pick/shaker, and a device to allow a tambourine to be played with a bass drum pedal. But for the most part, playing percussion along with another instrument seems to be a problem each of us must solve individually. If you have or know of an interesting, unique, or practical solution, please let me know!
Harry Bissell was kind enough to do so; he wrote:
I use an ultra-bright LED with a very narrow angle (18 degrees) shining on a phototransistor... this generates a pulse output that I feed to an Alesis D4. Break the light beam with your foot, and instant drum of your choice. (Mine is kick drum.)
I responded with a suggestion:
I use a Goodrich light-beam volume pedal on the output of my MIDI guitar-controlled synthesizer. A peek at its insides suggests that your system could be incorporated inside it to make a rugged and stageworthy controller. In fact, it might even be practical to control two sounds this way-- one toe-up, the other toe-down. And you might be able to find a non-working one inexpensively... :-)
I also have a HatKat clone (DrumKat ) that I made with an LED/Photocell inside a Moog 1120 (DeArmond made them) Foot Controller pedal. I bought it for $20; now they are worth $150 (vintage, you know...)
Your personal percussion prescription would be a great topic for discussion in the One Person Band Forum.
Like many others, I've tried to combine guitar and bass in the same instrument, with varying degrees of success. My most extreme, and most successful, attempt used a Fender Jaguar. I strung it .008, .011, and .014 on the top, with three bass strings on the bottom. Tuning was ADGCEA; though there was a big gap in the middle, chords and scales were just a fourth (or fifth) away from standard tuning.
I put this critter together one afternoon, and just as impulsively took it to a gig that night. It sounded wonderful, even without a bass amplifier. Unfortunately, I broke two high-A (first) strings in one set, so I retired the guitar for the night. Later experiments proved that the short-scale Jaguar could not produce satisfactory bass notes lower than the A of my original experiment, so I reluctantly shelved the idea.
Chuck Zwicky's Solo Looping Rig, though, includes a Steinberger guitar with a range of nearly five octaves.
Novax Custom Guitars also offers expanded-range guitars. Luthier Ralph Novak's fanned-fret instruments offer scale lengths which are several inches/centimeters longer for the lowest-pitched string than for the highest-pitched. He built the eight-string guitar plus bass for Charlie Hunter, and the seventeen-string "Guit-Harp" (actually, a seven-string guitar plus a ten-string zither) designed and played by Philip DeGruy (allowing him to do with one instrument the sort of thing Levi Chen does with guitar plus separate zither).
Roland allows you to extend the guitar's range electronically, rather than mechanically, with the VG-8 and VG-8EX and the new VG-88. These units, which require the use of a hexaphonic pickup like a MIDI guitar, can perform many of the functions of a MIDI guitar, while offering the numerous benefits of processing the guitar's own sound-- no cumbersome pitch-to-MIDI conversion is required.
This revolutionary processor is the subject of the V-Guitar Online Users Group's extensive VG-8.Com site. It's also the focus of a Connor Freff Chochran interview with Joni Mitchell, in which she explains how the VG-8 made it possible for her to resume performing music.
If you're into DIY live music, you may also be interested in DIY instrument building, recording, and distribution of your music.
Making any kind of musical instrument is fair game for discussion in the Musical Instrument Makers Forum (MIMF)-- acoustic, electric, or electronic, conventional or totally experimental.
While geared toward the recording of concerts, the DAT-heads site appears to be a treasure trove of information about digital audio tape recorders and their maintenence and repair.
The one Web site indispensible to anyone with any interest in any form of music technology is Harmony Central.