Stem, bars, seat and tires were all changed out. The rims are stock, though
. I'll find an older 26" Monocog for around $100 occasionally, but the 29ers are holding value pretty good ($250-ish plus). Especially the Flight Monocogs...I've been looking for an affordable one of those for a while.
All the ones I mentioned above are available in various sizes...usually around 15" to 21". All have horizontal dropouts, except the GT Peace 9ers, they have eccentric bottom brackets for single speed chain tensioning
.