holly, ivy, mistletoe, "kissing balls" (balls of greenery), anything with deer (yes they may ostensibly be reindee--also pagan-- but can double as the Great Stag!), LIGHTS (rebirth of the Sun/Son)...I will also sometimes arrange my tiny Xmas lights into the shape of a five pointed star (using strategically-placed tacks in the window). This is accepted as a Christmas symbol in most places...I also like using fruit in centerpieces with candles; very Martha Stewart but looks nicely pagan! Bowls of pomegranates with green apples looks very nice. You can also hollow out firm apples and place small votive tea lights in them...
I am having a big Yule party next weekend (local Boston area Mudcatters feel free to come!) and am getting excited about the decoration possibilities!
happy holly daze
peg