I've done stuff like this - just made a smiley face on the sign line. Never had a problem with it. It's funny though, occasionally at a very official place I've

I've done stuff like this - just made a smiley face on the sign line. Never had a problem with it. It's funny though, occasionally at a very official place I've had a staff member say my real signature that matches all my ID is too messy and ask me to write down my name beneath it in print. That happened to me at at least one or two consulates over the last few years when applying for visas. Also, I remember one time a friend got a 250 euro ticket driving through Austria, and I thought it was nonsense. He was speeding sure, but I think they inflated it by more than it was, and they said he had to pay on the spot or they wouldn't let him go. If I was in that spot, I think I'd write "Coerced Void" in artful cursive on the receipt and protest it later with the credit card company.