I was interested in the Holdsworth that was up for sale a few days ago and considering it for a porteur build but it didn't have double eyelets on the front fork thus nixing it as a potential porteur build.
Fast forward a few days later. I was poking around my local LBS and saw a clever porteur rack that doesn't require the use of eyelets. Perhaps this has been brought to our C&V forum before and if it has, my apologies on the double post. However, if not, then the Soma Porteur Rack is clever enough to be brought up.
There are a few reasons why I liked it. First, the obvious is that you bolted it to the hub axle. This means, no longer are two eyelets required on the front fork to mount fenders and a porteur rack. It also means no more quick release levers because of where the rack bolts on, but I look at it like this... if you want to make an omelet you have to break some eggs.
The other nice features is that the lower strut is available to hang a pannier and the extra eyelet is perfect for a dynamo light. A fence is also available as an add on.
It's a bit spendy but it's pretty nifty, no?!