I know theres a lot of you guys who ask questions about how to actually eliminate feedback, but I've heard lot of performances where sometimes the guitarist hits a single note and lets it sustain till you get the feedback sound, which is an effect I like a lot.

How is it usually done? Does it depend totally on the amp and what volume you play it at?
I wish I could play the clip of Spongebob where he and Patrick shout at Squidward: "TECHNIQUE! TECHNIQUE!".
lol which is why i posted under the guitar technique section of the forum...isn't the point to help you learn the technique?
Monsterous amounts of gain and volume. Mute all the other strings and a light vibrato should do the trick.

There are some notes easier then others, first start doing opens, then 12th then 5th and then where eva.

- Ibanez S470 (2004)
- late 70's vintage Fender Stratocaster (USA)
- VOX VT100 Amp
- Digitech Whammy Pedal
- Weeping Demon Wah Pedal
- Visual Sound Volume Pedal
- MXR Micro Amp