Turn on Mac with Tasker Is there any way to tell my iMac to turn on via tasker. If so, would both devices have to be on the same network? Is there a way to do this without being on the same network? Would my computer have to be plugged into the router or can this be done wirelessly? I guess I am trying to use wake on lan. So for instance, when I come home and tap my phone to a NFC sticker, my computer would turn on. Is this possible?
Yes, you are talking about Wake-on-Lan. And as far as I know, the device to be awoken this way must be plugged-in via an ethernet cable (how else? when it's turned off, so is its WiFi).

As for the network: either both devices have to be in the same network, or you have port-forwarding enabled on the router connecting the different networks (otherwise your target cannot be reached).

Now for the remaining part: How to use your Android device to trigger this? You were asking for Tasker -- and yes, that should be possible. There is a Locale Wake On LAN Plugin (and Locale plugins do work with Tasker. I cannot see that Tasker natively supports NFC -- but there's e.g. a Youtube video, so there must be a way -- hm, maybe this Locale NFC Plugin?

So now there should be everything complete, and you can start testing :)