We don't have anyone to watch our son. We haven't had a date outside of the house in over 3 years. My parents still work more then full time, including weekends. His parents live too far away. By the time we pay for a sitter, pay for dinner, or a movie, whatever...it's really not in our budget.
However, we have date nights at home. We have late dinners, where we sit and talk. We will both read the same book, and talk about the book after my son is in bed. We have a few games we love to play. We have a little two person fondue maker, and have fondue nights. We watch a movie together and eat pizza. (We usually do funny movies, because it's great to laugh together. Two of our favorite date night movies are The Other Guys, and Date Night.) We're planning on doing an outdoor dinner on the back porch, once the weather is right. We plan to buy a telescope and learn about astronomy together.
It doesn't matter WHAT you do, rather how you connect. We all need time to just sit and talk to each other. We make sure to keep the kid talk to a minimum, and also and stressful topics. We talk about the future, hopes, dreams, what we would do if we won the lottery, art, music, anything we can think of. For us, it's a time to relax, connect, and sometimes just be really silly. We don't suffer AT ALL, from not being able to do date nights out. Seriously!! When our son is in bed, he's there to morning. Our date nights don't feel different then being out, because it's an escape. It FEELS like a date, so that is all that matters!!
Do an internet search for at home date ideas, I'm sure there are many.