I haven't had much time to play with Tasker and only skimmed the documentation and what I read seemed hard to understand. Well, maybe "hard to skim" is a better description. Anyway, I thought it may be useful to someone to post a couple more examples I've found useful.
First:
Like most people, I leave GPS off unless I need it for a certain app. I usually forget to turn it on until after opening the app, then have to exit, turn it on and re-open the app, but now I have Tasker set to automatically turn on GPS when certain apps are opened. For this example, I will use the Maps app and here's how it's done.
Open Tasker and click "New" then "Application" and select "Maps" (or whichever app you want to use). On the next screen, click "+", "Misc", "GPS" select "On" and click "Done".
If you want it to pop up a message telling you GPS has been turned on, click "+", "Alert", "Popup" (or Notify if you prefer it in the notification bar), enter your text, e.g. "GPS Turned On" and "Done." You can also select how long to display the notification. The default is 5 seconds but I found 1 second to be better.
Now it will turn on GPS when the app is opened, but we also want to turn it off when it closes, so click Done again and get back to the main screen. Now click on the "GPS On" box and click "Add Exit Task". Click "+", "Misc", "GPS" select "Off" and click "Done". Again, if you want it to display a message when GPS is turned off, follow the same steps from above.
Now it will turn GPS on when you open the app and turn it off when the app closes. Pretty simple.
There is another way to set up this GPS On/Off task for easy repetition for multiple apps. From the main screen, click "Tasks", "New", enter "GPS On" or "GPS Off" then follow the On/Off setup above. Now it will be recorded as a task and if you want to use the same setup for another app, click "New", "Application", "+", "Tasker", "Perform Task" then select your task from the list.
Second Tasker use:
I have a short script here which employs an idea by Nathan Harrington from IBM. His perl script can be used to download a weather radar map from weather.gov, draw a custom-sized square around your location and check for precipitation inside that square.
Mine is what you might call a notification wrapper to his perl script and the end result is that it checks every 15 minutes and, if there is any rain within a 20 mile square centered around my house, it sends me an SMS saying "Local precipitaion detected." This has been extremely reliable for me and I usually get an alert 10-15 minutes before the first drop starts falling.
Whenever I get that message, I usually open WeatherBug and check the radar, so I set Tasker to open it for me. This is easily set up by opening Tasker, selecting "New", "Event", "Phone", "Received SMS" and entering "*Local precipitaion detected*" in the Message field. Once that is done, click the "+" on the next screen, select "App" then "WeatherBug."
I've also found a similar use. I went to two local news station websites and found good static weather radar images, copied the links and use the "http poster" locale plugin to download both images and the "Popup Image" Tasker option to display them when I get that SMS. These are quicker than loading the maps in WeatherBug and can quickly show if there is only one small spot of rain on the way or a big storm.
I'll leave most of this setup as an exercise to the reader, but I'll give these tips for using the HTTP plugin. Let's use "www.somesite.com/weather/radar/current.jpg" as the address to the file we want to display. Select the "HTTP Get" and type "www.somesite.com" in the "Server:Port" box. Under "Path", put "weather/radar/current.jpg". I'm not sure it's necessary, but under "MIME Tpye", I selected "image/*". Now put an output file and use that file name when you set up the next task, which will be "+", "Alert" and "Popup Image."
I'm not sure which of these I will use, but I've been having fun thinking of ways to use Tasker and simple tasks like these are pretty easy to figure out once you start playing with it.
Android and Linux