Mountain Lion - Preview fonts from the Fonts panel

When you want to see a preview of a font in Mountain Lion from the fonts panel, just click on the little dot under the title and pull downwards. This will reveal the font preview section of the panel. From here you can preview the font in whatever size or style you want. Also, you can make adjustments to the appearance of the font.
If you're not familiar with the Fonts panel it can be found in TextEdit by pressing Command+T or by right clicking on text or a textbox, going to Fonts and clicking Show Fonts (thanks OSXDaily for the 2nd method).
You can also manage fonts from the Font Book application.

AirPort Utility 5.6 and Mountain Lion

There are other posts about this on the Internet but I thought I'd make this one to collect all the information. 

The manual way - Using Pacifist

Pacifist (CharlesSoft) can be used to extract AirPort Utility.app from the installer .pkg file. This will allow you to run this version and version 6. More information is located here.

The automatic (ish) way - Using an Automator workflow

Several people have made Automator workflows for people who don't want to use Pacifist. One of these is located here.

Why use the older app?

There are 2 reasons why you may want to use 5.6 on ML:

1. You use an AirPort Extreme or Express 802.11g for some reason (e.g. music streaming, print server) and need to configure this on your ML box;
2. You want the additional features of 5.6 as some features (that I use regularly) aren't available on Utility 6.

AirPort Admin Utility (Graphite & Snow) on Mountain Lion

Doesn't work. Don't bother trying. What I do (if I ever want to set up a Dual Ethernet or Graphite base station) is go to my G5 (running Leopard). If your job involves doing this regularly and you have to use an Intel machine you might want to keep a Leopard partition around for this.

Do I have to do this with Lion?

No. The installer is made for OS X Lion.

MenuMeters - a great alternative to iStat Menus

MenuMeters is a menu bar application (OS X) designed to monitor your system. It is very similar to iStat Menus but it is free and the latest version works with PowerPC and Leopard.

It can give information on a whole variety of different aspects of your system, from CPU usage to network adapters. It can provide this information in a variety of different ways (such as a pie chart). In the above picture you can see MenuMeters in use on my Power Mac G5. It shows (from right to left) CPU usage, memory usage and the Ethernet connection.
Everything is customisable. The colours can be changed, as can the width of the graph, the percentage and the type of information shown.

More information can be shown by clicking on the menu bar. For example, here you can see what is shown if you click on the CPU usage graph. Uptime, processor type and load averages are shown (plus shortcuts to Activity Monitor and Console).

Overall, I think this app is better than iStat Menus and has the ultimate advantage: it's free. Download it from here.

Opening ports on a Belkin F6D4230-4

Just for reference, here's a guide on how to open ports on a Belkin F6D4230-4 (took me ages to explain this over the phone).

1. Go to http://192.168.2.1/ in your browser.
2. On the sidebar, move down to Firewall>Virtual Servers. 
3. Here it asks you for the router's admin password. This is not the same thing as the WiFi network password. If you don't know what it is you probably haven't set one, so just click Submit.
4. This is where you open ports. You'll need a static IP on the internal network to open ports to a particular machine. There are some suggestions at the top but some of these are outdated.

Generally, a better solution is to use UPnP (if it is supported by the server you want to use), which is enabled by default.