While the term baby shower is generally associated with the mom to be; now a days it is not at all uncommon to have a coed baby shower where both the mom and dad are present.
Why not make it something that both of them will enjoy.
Here are a few suggestions to make this type of party one that the daddy-to-be will not only remember but will also have a great time attending: Game Ideas: Have a casino theme for the games.
You can also take it one step further and perhaps have a golf party and have the celebration in the clubhouse following the round of golf.
The Food: Go with foods that scream "I am man hear me roar" ribs, burgers, steak, cheese steaks, wings, sausages and anything else you can eat with your hands.
Sloppy Joes are a good idea too.
If going coed be sure to have plenty of daintier options for the ladies.
Have some beers (or soda if you prefer) and barbecue.
The coffee and tea and cookies can also be there as a more traditional option.
Another good idea is having a cake for each of the parents, one geared towards daddy so he does not feel left out.
Remember, if dad is attending the baby shower it should be fun for him and his friends too.
There is also a good chance that the parents to be have common interests that might be a good theme idea where they both could have a good time.
You do not have to keep it totally separate, you can meet somewhere in the middle and make it a fun and casual affair.