Virtual instruments are a favorite topic of mine. Sampling and modeling technology makes it possible to play and record instruments that sound real - ARE, in fact, real in many ways - without having to have the actual instrument in your studio. And never mind the advantage - in certain cases - of not having to learn to play that instrument in real life. I put violins into this category. I tried. I really did. But I never got nearly good enough to sound like the virtual violins I can trigger via MIDI and "play" with a keyboard. So there.
Electric guitar is another issue. I CAN play guitar. And I DO have an amp. But I almost never record "the normal way," meaning with a mic pointing at the amp. I get to have tons of choices of different amps and sounds, with my amp simulator set-up, Pod Farm, from Line 6. I love it.
Here is and article with several tips on how to get the best results when recording an electric guitar without an actual amplifier. Check it out here: http://www.prosoundweb.com/article/six_tips_for_great_electric_guitars_without_amps/