Yes Craigslist is built to run at absolute minimum computing power. I would NOT suggest you follow her.
EDIT
Just because no one is wrong. I am not saying that the CL design was wrong. This is actually quite inventive. However, they developed the application a long time ago, and since then the transfer, processing and hosting services in general have become much cheaper. Essentially, I am saying that writing an application in the same way as it is now would be foolish.
Great love for CL though. Through this site I landed on several clients. :)
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