Below is a list of OSX apps that I use for web development.
Coda by Panic is what I always wished Dreamweaver to be. A simple, sleek interface with all of the tools that I need to get the job done. Gone are the days of unnessesary bloat and endless menus that plauge other editors (Dreamweaver).
Coda has everything you need for building websites, text editor + file transfer + svn + css + terminal + books + more. Woah.
Transmit is the definitive ftp client for the mac. Whether you are transfering files with FTP, SFTP, WebDAV or Amazon S3, transmit handles it all, and fast.
There are some free and open source alternatives, such as Cyberduck
MAMP sets up a local "Mac, Apache, MySQL, PHP" development environment in a few clicks. Install MAMP, then in preferences change the Apache Document Root to your sites folder, and voila! A local running php test environment.
It comes default with common libraries compiled such as curl, gd library, and more.
You will invevitably come across an archived file that you cannot open. Either it was packed in a .rar or stuffed with stuffit. Install the Unarchiver and open many more types of file formats than the built in unarchiver in OSX can handle. Like a swiss army knife it'll open just about anything.
There once was a day when remembering a password or two was no big deal, now some of us (me) have hundreds of passwords. Never forget a password again. Manage passwords, software licenses, credit cards, and more then sync them all to your iphone.
Sure PHPMyAdmin gets the job done, but probably in twice the time it will take you to edit your local or remote MySQL database in Sequal Pro. Need to send a database schema to a client? Forget drawing it up in a graphic program, simply create your tables, export to a Graphiz dot file, then to .pdf.