Recently I came across a site which had some of the Skype Hidden Emoticons.
As I was interested in identifying if this was an exhaustive list I loaded the skype.exe file into a HEX editor to have a look around.

Here is what I found:

(inlove) (love) (cry) (surprised) (smile) (cool) (wink) (sweat) (sad) (surprised) (speechless) (kiss) (tongueout) (wonder) (snooze) (dull) (inlove) (love) (grin) (talk) (yawn) (puke) (angry) (wasntme) (party) (worry) (mm) (mmm) (mmmm) (nerd) (wave) (hi) (bye) (call) (devil) (angel) (envy) (wait) (hug) (bear) (makeup) (kate) (chuckle) (giggle) (clap) (think) (bow) (rofl) (whew) (happy) (smirk) (nod) (shake) (punch) (emo) (y) (Y) (ok) (yes) (n) (N) (no) (handshake) (skype) (ss) (h) (H) (l) (L) (heart) (u) (U) (brokenheart) (e) (m) (mail) (F) (f) (flower) (rain) (london) (sun) (o) (O) (time) (clock) (music) (~) (film) (movie) (mp) (ph) (phone) (coffee) (pi) (pizza) (cash) (mo) ($) (flex) (muscle) (^) (cake) (beer) (bricklayers) (d) (D) (drink) (dance) (ninja) (*) (star) (mooning) (finger) (bandit) (drunk) (smoking) (smoke) (ci) (toivo) (rock) (headbang) (banghead) (poolparty) (hrv) (swear) (bug) (fubar) (tmi) (heidy) (myspace)

This is what they look like when included in a Skype message:

Here are then smilies:
😀 😀 :=D :d :-d :=d 🙂 🙂 :=) 😎 8=) B-) B=) 😉 😉 ;=) ;( ;-( ;=( (:| :O :-O :=O 😮 😮 :=o 😐 😐 :=| 😛 😛 :=P :p :-p :=p :^) |-) I-) I=) ]:) >:) :& :-& :@ :-@ :=@ x( x-( X( X-( x=( X=( :S :s :-s :-S :=s :=S 8-| B-| 8| B| 8=| B=| 😡 😡 :X :-X :# :-# :=x :=X :=# 😕 😕 :=? o/ :D/ :d/

References to Skype Flags
http://www.semanticpool.de/hidden-skype-emoticons/