Ever wanted to write in "عربي" as fast as you write in "3arabi" ? Confusing, no? I'll explain...
Simply write in arabic with roman letters and Microsoft Maren will convert the word to arabic text. I haven't tried it because it's a Windows plugin but I think it's promising.
Lack of access to an Arabic keyboard or lack of familiarity with one are two of the most common problems preventing Arabic users from communicating in their own language.
Microsoft Maren is a Windows extension that comes to the rescue, allowing you to type Arabic in Roman characters (Romanized Arabic, Arabizi, Arabish or Franco-Arabic) and have it converted on the fly to Arabic script.
Maren integrates seamlessly with Windows and works in most Windows applications and websites.
I'm still not sure but I think there's one serious downside to it too. Looks like it translates to Egyptian only. Maybe there will be more versions soon.