Hello again Nick!
Having played around with your image RSS feed for a while on my own site and on a client's new site, I though I would point out a couple of things I have learnt/am learning, and also hope you can offer some help/advice.
Firstly, for those that have been asking about adding borders etc to individual thumbnails with the basic iFrame version, you can of course do this by overlaying a new div containing blank boxes with the border that you want. You can also hide a particular thumbnail if you want an irregular spacing between thumbnails by overlaying a thumbnail sized div of the background below. All this is a very messy way of doing things but if you dont want to get into the PHP versions then you can do most things that way - have a look at the footer of my page: HCD Home
Secondly, for those wondering how to select only images from a multi-content RSS feed (such as Tumblr) being used for the photo feed, you can filter out other content (and do a million other things to your feed) by using Yahoo Pipes. Pipes essentially takes in a standard feed, lets you alter it in a huge number of ways and then outputs a new, altered RSS feed. Unfortunately (Nick this is where I need your help) because the RSS feed address it outputs is a URL query string containing ampersands etc, Nick's iFrame version is getting confused with the variables that are attached to the end of the RSS feed and so the whole thing won't display...
Nick is there any way of splitting the variables that in the iFrame are attached to the feed? (&thumbsize for example) If this isn't possible in the HTML version, would I have the same problem with the advanced PHP version? I just want to know before I take a crash course in PHP!
If it helps, this is the new Pipes RSS feed:
Hope this all makes sense..! Cheers in advance for your help Nick.