Thinking of making a few signs for IMC and I know there are some great ones. Here is all I can remember.
HTFU
Toughen up cupcake (or Princess)
If it was easy, i’d be called football
John 3:16
Free Beer
I know there are better ones…?
My all-time favorite:
“If you can read this sign, then you need to speed up you pussy!”
.
TRI
+
UMPH
TRIUMPH
DONT SUCK.
“IRON ELEPHANT” (with a rear view of an elephant w/ an m-dot on its butt…sounds stupid, but it was pretty funny at mile 23 of the marathon if only because it was so much different than “GO JOHN #456”.
“Whats YOUR reason?”
Or, throw a sign out there that says “honey, i’m pregnant”. That got some people talking at imaz '07…
Why would John 3:16 be a good sign to hold up at a race?
Oh - and “Free Beer” had better be true, or you might end up with a lot of pissed off racers!
John had a Boston Qualifer for a 40 year old dude
.
I’ve done:
Nice Legs (got great response from racers)
SMILE you’re an Ironman (at which 99% of racers smiled)
.
Best sign ever:
“Captain Canada is so hot”
just a suggestion …
The signs we used for last years IMC were:
“Ride like you stole it!”
“We love IronWomen”
“Pain is temporary; Quitting is forever” ← this one recieved a few dirty looks
but also good is:
“Embrace your inner Kenyan” and
“Don’t be a disappointment!”
.
“Last Hill”
“Opps, Next to Last Hill”
“Ice Cream Station Ahead”
.
especially of wearing light colored shorts…
It’s a series of signs.
The first sign reads: Mike I’m pregnant!
The next sign reads: It’s not yours 
Seen at IMWISC:
You look like hell,
You’re not almost there,
and it’s mostly uphill from here.
“When you get to the end of your rope, tie a knot and hang on” Franklin D Roosevelt.
This kept me going on my first marathon Twin Cities at about mile 22 as we started climbing the hill.
At IMLP in 2006:
“Go faster, Daddy. Mommy wants to go to Hawaii.”
It’s a series of signs.
The first sign reads: Mike I’m pregnant!
The next sign reads: It’s not yours
I remember laughing at that one…IMAZ!
One I like to yell and always get a response:
Looking Sexy!!
Women usually laugh. Men grimace. 
I also like
Cowgirl Up!
or
Cowboy Up!
**
For Richter or Yellow Lake:
**
Pedal harder!
**
I saw at IM Fla last year:
“Holy Fuck I’m doing an Ironman” - Made for a great laugh 80 miles into the bike
“Don’t be shark bait dad” - being held by kid on someone’s shoulders at the start
.
Check your saddle…you just launched your bottle
Your socks are falling
If you dropped a few more pounds, this hill might be easier (applies to me)
.
One of Frank Lowery’s signs at Silverman:
“Suck it up Buttercup.”
Made me laugh for a few miles.
Personal ones are most memorable. I was seeing a girl who a was also a triathlete and she gave me some signs to take - she couldn’t go to the race but they were for my mom and sis to hold.
One was “Goo Captain Homeschool” (nickname - I did not go to homeschool).
The other was a Battlestar Galactica reference I can’t recall exactly.
It was quiet nice because for years I had seen others with personal signs and this time I had some to.