The rules for smartlinked guns say that this enhancement can be used to shoot around corners. I don't think there exist any RAW penalties for this, but if not, then it seems like the sort of thing you would do all the time. I apply a -2 penalty for the awkwardness of the position, plus double unmodified recoil penalties due to the fact that you won't really be able to brace yourself. Does this seem reasonable? Do there exist actual rules for this somewhere?

Shooting around a corner, normally, would be shooting blind (-6 dice, and intuition rather than agility, IIRC). IMHO, Smartgun's guncam would negate this penalty at least, but the sort of additional situational penalties you're describing would affect both modes, equally, if you decided to apply them. Also, in both cases, since you are taking cover (from the corner you are shooting around), you would take an additional -2 penalty. Personally, I think the -2 penalty for firing around cover already covers the inconvenience of the position, but the rules don't expressly cover a situation in which a character chooses not to brace against recoil.

Nope, it's been discussed here a few times before.
I go with double uncomped recoil for shooting and make them roll strength + reaction (uncomped recoil) to see if they can hold onto the gun if they abuse it (reasoning that if you're quick enough to react to the wild flailings of the gun you can use your strength to hold onto it better).

Shooting Around Corners aka From Cover, Smartgun System (Smartlink) has a camera....

Shooting Around Corners, Giving in to the Cheese Side

Here are a few that I am aware of, having participated in them.

And my short and sweet would be that I think the existing penalties are just fine and using a gun cam is not shooting blind ... unless perhaps someone knocks your linked contacts/glasses/goggles off.Shooting Around Corners aka From Cover, Smartgun System (Smartlink) has a camera...

Thank you for the links - however, the first one is broken. I imagine you meant to link here?

Anyway, this gives me enough information. I think I'd rather just treat it as normal firing from cover, even if it is unrealistic that you get the same penalty with just your hand sticking out as you would with 1/3 of your body visible. There are enough finicky little combat modifiers as it is.

Ack, I almost totally failed somehow on my copy+paste, guess I rolled a critical. Sorry about that and yeah, that was the thread I was trying to link to.