I don't know about you, but my dad is really hard to shop for. He buys everything he needs or wants. And when you ask him for ideas he suggests things like black socks or white tees. "No dad, I am not stocking your underwear drawer for Christmas!" Us kids are pretty much resigned to buying him movie tickets and cashews year after year. And I think he actually gets more excited over those simple treats then the times we try to buy him expensive gifts.
With that said, I hope you dad is easier to shop for! These fun Monopoly car cuff links are $20 at Lizzie Blue's Shop on Etsy. Not quite his style? A quick search on Etsy brings up all types of individualistic cuff links.
Go big: Buy him personalized cuff links. Try cufflinks.com or Things Remembered.
Other ideas for dad: A monogrammed steak brand from William-Sonoma for $39.95, gift certificate to Omaha steaks, spice rubs $24 for set of 4, power tools, sporting equipment, camping gear, MP3 player, digital video camera, flat screen TV, a new leather wallet, sporting event tickets, concert tickets, or a gift basket of his favorite snacks & drinks [like cashews =)].