Macfarlane + Green Architecture in Vancouver BC coverted a large box retail spot into a college building that just won an award.

I've worked on a project that converted a Super K-Mart big box into tinier boxes.

look at lewis.tsurumaki.lewis. they have done some speculative projects with big box convertions. enric mirralles - rehabitation santa caterina market. also, take a look at wal mart's projected growth. for the 2005 FYE they planned on 50-55 retail centers, 220-230 supercenters, and 25-30 neighborhood markets. as of april 2004 there were approx 3500 wal mart stores on this planet. so if you do come up with a good plan you will have quite a few opprotunities to impliment it.

I'm working on a small big box remodel right now. Not a Walmart. Ask me anything. I'm brilliant.

i'm working on a speculative landscape installation in a defunct wal-mart [they built a new one - bigger and better about 3 miles away]. We're constructing a giant terrain covering the entire groundplane. I'm mostly wondering what kind of problems people have had with the existing structures, especially the subgrade.

my firm is working on converting a 375,000 SQFT former circut manufactuing warehouse into a school and supporting disctrict facilities.

I also once took a great big box and made a rocket ship. Man, that was cool.

Not the most beautiful projects, but they are reuse of big box.
http://www.bigboxreuse.com/

I think this is a better conversion.
http://images.google.com/imgres?imgurl=http://www.jecrain.com/assets/armoryoaks2.jpg&imgrefurl=http://www.jecrain.com/armoryoaks.html&h=324&w=410&sz=76&hl=en&start=1&tbnid=tXSAhgKCbClYeM:&tbnh=99&tbnw=125&prev=/images%3Fq%3Dgateway,%2Bsoutheast%2Bventure,%2Bnashville%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN

Here is another image of a computer model of it.
http://ll.bizjournals.com/cre/listing/nashville/752407