As part of my practice regime I jam over backing tracks (as I am sure many of you do). I now use a Boss E-band and upload the tracks I like to it. I tend to play anything I want over the backing track once I have found the key / scale that is appropriate.
Yesterday I was playing over Guns n Roses "sweet child o mine". I did the intro as per the record, the power chords, etc, I know the first three short solos fine. But when it comes to the final two fast solos, I dont know these so I simply freestyle it out of the Em pentatonic / blues scale and do my own thing - not trying to be like the record. In the middle of practice, I just played (as if from nowhere) an amazing (for me - a newbie) run of notes or lick and at a speed I had always felt was unattainable!
It came from nowhere and was a run from the high e-string all the way down to the low e-string and swapping between positions really quickly and note perfect. Firstly, I was so stunned I stopped playing - it did not 'feel' like me. Secondly, I tried immediately to remember what the hell I did, so i could repeat it - i could not. Rather like an alien abduction experience - i cannot prove any of this to you

However, do you often find in practice - 'things' just happen that surprise you and sometimes you simply cannot remember what the hell you just did - but it sounded ace....