After you've got PHP5 and Apache running on your Ubuntu development server, the next thing you'll want is Eclipse PDT. Shortly after that you'll need a debugger.
On Ubuntu 8.10, I set up Eclipse 3.4 (Ganymede) with the latest Release Candidate of PDT 2, it took forever because of some slow mirrors, but I'd recommend just buckling down and getting through it. Here's the step-by-step guide I found most useful. If Ubuntu someday gets PDT and Eclipse 3.4 in the repositories then just use that.
Waterloo has a Drupal developer group and they're getting together tomorrow night. James Walker (of Bryght/Rain City Studios/Lullabot fame) is going to be there talking about module development. It'd be a 3 hour drive for me to get to a 2 hour meet up but I seriously considered it. I've been learning module development off and on for a couple years now. I've actually done a couple for personal use. Sharing experience in a group like this is a lot of fun and you get a lot more insight in person than you can by just reading. I'd encourage anyone nearby to head on over and check it out.
Does Windsor have enough Drupal developers for a Drupal group? Do we have enough LAMP developers to support a group? I like the Windsor Blogger meetup we've been doing (more bloggers welcome, btw). The blogger meetup seems to have been going long enough now that it's a regular thing. I'm a little jealous of Waterloo, they have about the same population as Windsor. I think we should have enough developers to get together and share some ideas once in a while.
CakePHP uses the Prototype Javascript library for its ajax helper class but I've come to prefer jQuery. Prototype is a fine library too but I've just gotten used to jQuery.
A web application I'm working on needed a ttw html editor so I grabbed TinyMCE and copied in some of the example code and everything seemed to work fine at first glance. Unfortunately TinyMCE has an issue with jQuery's $(document).ready function and it also has an issue with saving via ajax in CakePHP.
There's a helpful page on the Bakery that outlines some issues you'll run into trying to get CakePHP & Prototype working with TinyMCE but it's a little out of date now (I'm using CakePHP 1.2RC1, TinyMCE 3.09 and jQuery 1.2.6 at the moment). I'll go through examples that illustrate how I solved the two problems I ran in to but I'm not going to explain everything you need to do ajax submissions with CakePHP.
Here's a quick tip for PHP error reporting and display in development.
When a project is in the early stages of development you want to see all the error information you can. You probably want E_STRICT on especially when you're starting from scratch, to help avoid relying on deprecated behaviour. The E_STRICT flag is only available as of PHP 5 and is not included in E_ALL until PHP 5.2 (there's a little disagreement on php.net between the definition of E_ALL in this table and the earlier note about error_reporting on the same page).
In an early development project you also don't want to have to keep tailing log files to see the error messages. That's a pretty sure way to miss errors. So you want to set the display_errors flag on. You also want to control this on a per-project basis, since some projects will have legacy bugs that you're not fixing right now and those can be left spouting errors to logs until someday in the future when you decide to fix them.
config/config.php:
$smtp_auth_mech = 'login';
The default was none.
So overall all you need to change in the default config file to make SquirrelMail work with mail at 1and1 are the $domain, $smtpServerAddress (smtp.1and1.com) and $imapServerAddress (imap.1and1.com).
The other interesting thing is that since SquirrelMail is just an email client, you don't have to run it on your 1and1 web server to get your 1and1 mail. If you have a home server or one hosted somewhere else, you could use the same configuration file and SquirrelMail will go get your mail just like any other client would. Depending on how you use your mail you might find this a little more convenient and possibly faster than using your web server.