Here are a selection of pin-ups I've done. All conventional wisdom says don't show pin-ups as editors aren't interested, mainly because they won't hire you to do covers... well, it's EXTREMELY unlikely anyway.
Creatively and as exercises for keeping your enthusiasm up, I think they're worthwhile doing from time-to-time. I think they're a great way to provide interesting variety in your portfolio also.
I'm not 100% sure about showing them to editors or not but I do think you can grab attention a little bit with them.
Again, entering into the spirit of courting criticism. Something I submitted to a chap who prints (art) books containing lovely pictures by some pretty cool individuals.
link 
This second one was done as another 'cover' excercise and as a submission to a
blog that I thought was kind of funny.
The next one, I've shown to Tharg and his comment was that there was something off in the foreshortening of the arms. Fair comment I think - I still think it's a pretty cool pin up and I'm not unhappy with it, but I can respect the criticism because I can kind of see what he means.
I was lucky enough to have received a bit of help on this one from PJ Holden who made some great modifications early on:
...I've made a couple of MINOR mods to your dredd pic, which, I think, makes it slightly more '2000ad'
The first: I've increased the size of Dredd's left hand - foreshortening. It's a great pose - but needs a little more push!
The second: I've decreased the size of Dredds helmet... call it personal preference, if you like (and it probably is) but I think Dredd's helmet needs to appear as part and parcel of his head - so tightly fitted and snug that that chin and helmet are one unit.
for ref, this was the original sketch and the revised version:
...and I had some pretty enlightening crits from Dylan Teague too:
"...overall I think it's a nice pic, good perspective nice colouring and solid drawing. The problem is, it just isn't Dredd, he's not powerful enough and even looks a bit vulnerable in this scene. It's not a case of his physique, though his head could maybe be a little smaller, its more down to his attitude and framing in the drawing. I think a lower angle would have helped so that he wasn't overpowered by the buildings, remember, it's Dredd - he has to dominate the pic!!"
Things there to be borne in mind - not only for pin-ups, but for strip work... I think certain inherent errors I've been making are clear from the comments made, and that made the pin-up all the more valuable to me as I have garnered some real insights into what Dredd is about, how he is viewed and the technical things I need to look out for. Within the confines of a strip where there are many other considerations - it's probably easier to overlook that which is staring you in the face!
