Direct marketing testing is both art and science. Here are three situations where “statistically significant” results might not have business significance.

Helpful info from PayPal: fake credit card numbers with valid checksums, good for test orders.

Interesting free and/or open source alternatives for handling online meetings, videos, screenshots, and files.

Back from TED in March: Blaise Aguera y Arcas’ PhotoSynth demo. Stunning technology from Microsoft Live Labs for building 3D models of the world from collections of regular snapshots.

Online marketing is evolving so quickly, there typically isn’t time to engineer the “perfect process” out of the gate.

Links to some recent articles I wrote for Catalog Success magazine.

Five interesting resources on setting up top-notch 404 “Page Not Found” pages.

My shower sprung a leak. Google hands me a scarily perfect search result. AI is just very large scale computation, Larry Page predicts.

You can clean up your Microsoft Outlook contact list using Excel, easily and at no cost.

As many web marketing programs are managed through web apps, a little browser hackery can go a long way towards increasing the efficiency of the web marketing team.

We’re pleased to sponsor YAPC North America, next week in Houston.

Went to BeCamp, my first un-conference this last weekend, and it was great. If “all the good stuff at a conference happens in the hallway”, an unconference is way to have nothing but “hallway”.

Yesterday Yahoo announced they are opening up the API to their new search platform (aka “Panama”). I caught up with Dan Boberg, Yahoo’s Managing Director of Sales Technology by phone yesterday to talk about this API announcement.

The open source software movement never ceases to amaze. Beyond the wildly successful open source behemoths — Linux, Apache, MySql, etc — there’s a whole ecosystem of amazing little apps like TrueCrypt, SevenZip, and OpenVPN.

Last week I had the opportunity to try two new operating systems: Vista and Ubuntu. Both worked great. Ubuntu impresses, even on four year old hardware.

Need a temporary email to receive a registration from a website? Try Mailinator.

If your own IT wizards are responsible for the care and feeding of your web app databases, I highly recommend this series of fascinating posts on database strategy put up by O’Reilly last spring. Tim O’Rielly interviewed prominent web sites on the nuts and bolts of their database approaches.

Hardening an e-commerce web site is hard, and too many web retailers underestimate the risk of attack.

The folks over at Wesabe describe a neat idea for protecting private data in a database: they call it the “privacy wall.”

Hadn’t known Excel allowed custom graph types — a real timesaver.

Inbound links are precious. Not only do they matter to search engines, but they reflect the interconnected relationships of pages and people and ideas on the web. When reorganizing your site, don’t break the old links. Redirect visitors to the new URL.

My Outlook PST file died badly this week. The key steps for me to recover the file was scanpst.exe and using Outlook’s “Export As PST” functionality.

Ever ask, “How much more or how much less ought I be spending on advertising?” Here’s a simple model with accompanying Excel spreadsheet to help answer this question.

Yahoo Pipes is a beta Yahoo service that allows non-programmers to create RSS mashups.

Rosenberg tours many of the key ideas and people of the modern software movement. Kudos for smartly organized writing covering a lot of difficult terrain.