The Internet is full of all kinds of interesting tools and simulators. It seems no more than right that musical performance should fall into the category of disciplines represented by the overwhelming existence of digital counterparts. A quick Google search for “virtual musical instruments” will lead a user to a host of sites that are some how associated with digitally simulated instruments.
Wesleyan University offers an entire online museum of virtual instruments of all sorts from across the globe. The Department of Canadian Heritage hosts an online museum with an entire section devoted to a grid of virtual music-makers. Jim Doble maintains a site called Elemental Design that is dedicated to various percussion instruments. The site contains a section devoted to uncommon virtual instruments filled with various virtual, such as the pipe harp, the pentatonic aquarion, and such experimental instruments as a wrenchaphone (a xylophone made with wrenches). David Holmes has compiled an entire Museum of Sound Toys that provides a large collection of links to musical instruments online.