Brace placement style. A lot of people tend to be very religious about this.

# The best way...
if (something)
   {
   do something;
   do some more;
   }
else
   {
   whatever;
   whatever;
   }

# The acceptable style:
if (something)
{
   do something;
   do some more;
}
else
{
   whatever;
   whatever;
}

# The classic K&R style (ugh):
if (something) {
   do something;
   do some more;
} else {
   whatever;
   whatever;
}

# The conversational style...
if (something) {do something; do some more} else {whatever; whatever}
[download]

I'm not sure if there's any major variants that I've missed.