Have you received quick message today? ;)
 
Although we don't need quick messages on this site but as they say "diagram worths many words".
 
Spend 15 minutes and your users appreciate your efforts.
 
1. Find two animated icons: one for wink and one for kiss. You may take mine though I'm not sure about copyrights. I don't remember were they free or paid.
Upload icons to your website. Let's say '/media/quick_gifs/' folder.
 
2. Open CP->Settings->Quick messages and edit them accordingly:

and
 

Almost done.
If we send quick message now we get '<img src="http://www.yoursite.com/media/quick_gifs/wink.gif" alt="Wink" />' as is. That's happen because all messages cleaned up before displaying for security reasons.
But we can trust quick messages as we trust News made in CP and enable html for them as well. Let's do it in the next step.
 
3. Open /includes/lib/lib.account_messages.php and find function show_message
 
Around line 1170 (commercial version) code:

replace with:

Now we trust quick messages yet clean up regular messages.
 
Voila!
 
Want to play with it more on this site? Use u: demo, p: demodemo as sender/recipient account.
 
P.S.: You can give your users a lot of fun during St.Valentine's day, Christmas, Halloween creating beautiful quick messages and giving your members one click link.