Remove duplicates from a list
Remove one list of values from another list
Format line widths for text emails
Calculate web site sales numbers
Direct Marketing Calculations
Evaluate your website copy for rational vs. emotional words
Evaluate your website copy for adjectives
Check your compact P3P policy
Create high-response form buttons
Extract Aweber Data
Dynamically Personalized HTML
Great post about how the author found a void when looking for a solution to a problem he was having with his cell phone
Great page of PHP SEO Scripts for doing Search Engine Optimization
Testing is probably the most effective way to optimize websites. Through testing we can understand what our customers like, which ultimately will help us create a better customer experience for our audience. But "our audience" is usually not a unique type of person; it is important use techniques such as Test Segmentation to understand the differences in the tastes of each cluster of customers.