Well in response to the other thread. I decided to make a little guide of my own, teaching you how to forward your notifications of new PMs to your Wii.
1. Make sure that your favorite forums has your Gmail account set as your primary e-mail account. And be sure that your preferences on the forums is set to send a PM notification e-mail.
2. Send your e-mail account a friend request from your Wii. To do this goto the 'Message Board' from your main Wii screen. Select 'Create New Message', the icon that looks like a pen writing on paper. From there select Select 'Address Book'. Select 'Register' and choose 'Others'. Insert your Gmail e-mail address like so.
3. Now for the computer side of it. After your Gmail receives the confirmation e-mail from your Wii reply to it to allow e-mails to be sent and received from your Gmail and your Wii.
4. Log into your Gmail account and select 'Settings'.
5. From here select 'Filters' then 'Create New Filter'.
6. Set it so that all e-mails with the word 'Private' in the subject is the criteria of the filter. Then select 'Next Step >'. It should look like this.
7. Now simply click the check box that is next to 'Forward it to:' and then put your Wii's e-mail address in the text box to the right. (To find this e-mail address its the same address that the confirmation e-mail was sent to and should look something like 'email@example.com m'.) When your finished it should look something like this. Now click 'Create Filter' and your done.
Your Private Message notifications should be forwarded to your Wii. Making a nice blue glow whenever you receive a new PM, so you never miss a PM while gaming.
To have any e-mail forwarded to your Wii simply follow all the instructions above. But when creating a new filter, have the criteria for the e-mails to be forwarded be. "Doesn't Have:" have the criteria of "zzz." This will send almost all e-mail sent to your inbox (spam still goes to spam only) to be forwarded to your Wii.
I hope this guide is useful to somebody out there. And I'd like to give full props to Neodudeman who actually was the first to come up with the idea to send notifications to the Wii.