It's a mobile world, and the same is expected of developers. You cannot always be next to a computer, but you can take steps to help solve a crisis without ruining your day.
If you do not read Smashing Magazine yet - you really need to head over there.
Watching file sizes and following coding standards are only one simple way to optimize your website. Proper HTML will ensure you page is processed as smoothly as possible, but does not mean a major speed boost. When the dust settles from developing a new website, I turn to Google's PageSpeed for the round up of last minute tweaks.
Achievements seem to be popping up in every new web service. Why? Because achievements make you win the Internet. Okay, not really, but it does make your user feel more engaged into your web site. It gives the user a reason to use your site and do more things on your site. The best part is the achievements do not even need to be all that difficult.
When developing web applications it is always wise to use the most up to date APIs and know when to scale back on certain functionality. Google just posted a blog entry stating four mobile web app tips when using Google Maps.
I know when I first started out learning PHP it was difficult finding good examples or live demos of simple PHP in use. Often I'd have a large number of files used to demonstrate built in PHP functions. So, to help any budding PHP developers out there I compiled a list of the PHP Server variables along with what data they provide. $_SERVER variables can be used in multiple ways from getting information about your visitors to script security.
SR Photography offered a nice gesture, if I created a PHP back-end contact form they would take infant pictures of our new born son. Created a short and simple PHP script with field validation (NOTE: Did not design site or form, just the back-end functionality of the form).
Two years ago I decided to check out an old gaming group that I used to play with years before that. I created a plugin to seamlessly add a ladder system into their web site. A ladder system is typically used to match one-on-one matches. This allowed the group to add friendly competition without major overhaul of their web site. I only made one version, but I plan on developing it a little bit further. The script allows for multiple games,which are dynamically set, and requires only one additional SQL table.