UPDATE on 11/16/2022 – This post was written several years ago and is still very popular on my blog, so I decided to do an update. If you are working for a non-profit and using the Nonprofit Success Pack (NPSP) and CumulusCI, then you should strongly consider looking into open-source Snowfakery to generate fake data that adheres to relationships.
I am currently designing a course for lynda.com about improving Visualforce performance. I decided that it was necessary to load my Developer org with a bunch of fake Account data in order to demonstrate some of the performance improvement techniques I was suggesting. I am NOT talking about unit test data, but actual data (just randomly generated). I have tried to generate things like this in the past and it always turned into a big pain. So I went ahead and did some general queries to see if anyone had already slayed this dragon.
At first I was excited about an article I found on DeveloperForce about Generating and Loading Representative test Data for Salesforce and Force.com Orgs. Perfect, I thought. That is just what I need. Unfortunately, I needed it fast and this article details a painfully long way of generating a Ruby on Rails app and installing all sorts of things that I really did not have the time for. I have worked with RoR a bit and knew this method would take way too long.
I did not want to create my own custom Apex factory or install some expensive app off the AppExchange. So back to searching and then I came upon the website GenerateData.com. I was a bit skeptical about it working, but in less than 15 minutes, I had generated my first data set for 100 Accounts and loaded it into my Dev org. I had hit the fake data jackpot!!!!
Now in all fairness, it did take me a few more tries before I got the data exactly the way I wanted, but this method was definitely fast and effective. I will also tell you that you are limited to only generating datasets of 100 records at a time using the Free version, but if you are willing to pay a very small fee (which I was, since I think it is a GREAT deal for all the time it saved me), then you can save data sets and generate as many records as you need.
And to save you a little time, I am including a screenshot of what my final Account Data Set looked like.
With my paid account, I generated 1000 Account records and imported them using the Data Import Wizard in Setup | Data Management. It took me less than 2 hours to get all the data loaded exactly as I needed it. I consider that HUGE!!!
I hope you find this tool as useful as I did. I sure do appreciate the developer, Ben Keen who wrote it! GREAT job!!!!