I have been building models of all sorts for about 35 years. Plastic scale, RC scale planes and boats, etc.. About 15 or so years ago, I switched pretty much to just scratch building everything. Some of my stuff is in RCAF and RCN museums.
One of my favourite plastic kits is the 1:72 scale Flower class corvette. You can see a couple samples of my work here (in various states of completeness)
http://www.rcgroups.com/forums/showthread.php?t=208966#post1933949
Both are loosely based off of the Matchbox kit but have been heavily kitbashed to different ships. The top one, the HMCS Sackville is modelled after the last existing corvette docked in Halifax Nova Scotia.
The bottom one HMCS Vancouver, is extremely heavily modifed. Pretty much only the hull and funnel from the kit were used, the hull had major surgery done on it.
The really great thing about the corvette model is that no two real ships were ever the same, and the same ship was rarely in the same configuration for more than a few months. So that one kit, with some skill and effort, can be turned into a limitless number of subjects. And they were always pretty beaten up too so lots of good weathering opportunities.
You can see my scratch building work here:
http://www.rcgroups.com/forums/showthread.php?t=207686
This is a 100% scratch build model of a Canadian Patrol Frigate. The hull was built from fibreglass (via a mold I created), the upper decks are vacuformed and sheet styrene. There's some photoetching and resin detail as well that I built. I create my own resin molds and do my own photo etching. Raw materials excepted, nothing on that CPF was a purchased part.
What you see there is a couple years worth of work, and it's far from completed.
"They're not dolls. They're action figures. Valuable Action figures!"