Tone can be expressed over text on the internet, details inside.

[Populus Romanus]

Interrobang is an excellent idea, others not so much.

This should be i n watchtower.

[A Nerd]

Moving to Watchtower.

[Skullheadhq]

Interesting story¡

[Peasant Phill]

Perhaps typing "[/SARCASM]" or something similar can do the same and be a lot clearer than a symbol that few people know about.

[Populus Romanus]

But I like the interrobang. It is very clear and easy to understand. Why not have it‽

[a completely inoffensive name]

Perhaps typing "[/SARCASM]" or something similar can do the same and be a lot clearer than a symbol that few people know about.

But that strips the sarcasm of any elegance it might have. It's very blunt and takes away the ability to enjoy it because your eye spots it immediately and prepares you for it, which ruins the effect of it. A different punctuation mark allows for the reader to go about and take in the sentence without any presupposition of its contents and then receive the context at the end.

[Tellos Athenaios]

I'd rather have support for markdown or restructured text than something obscure which few people will understand. Especially if the aim is to improve on semantics which are in any case supported well enough through more eloquent use of English, implicitly understood, or easily made hinted at in other ways. The ORG has a particularly fine collection of smilies, for instance.

[TinCow]

Tellos' concerns are mine as well. The proposed punctuation would work well... if it was commonly understood. I doubt most people would know what they meant if they showed up in threads, which would defeat the purpose of using them. I'm a pretty well-read guy, and even I wouldn't have known what they meant if someone had posted them in a sentence prior to the creation of this thread.

Interrobang I think is commonly understood, but no matter what we did it would be far more work to type the code for that icon than to simple type ?!. Where's the time-saver there?