But it's hard to get any investment, pay any bills, or hire any employees if you don't at least have a plan to make money in the future. Don't say "I have no clue", say "I'm focusing on growth now. Profit will come later."
If you make a good product, it may or may not make money but you might make more money by having the experience of making something. It it's cool, it probably will enhance your portfolio.
If you're in it to just make something cool, then do it. Sadly I think that with all the focus on startups here, the "hacker" in "Hacker News" gets forgotten sometimes.
tl;dr - get out of the office and talk to prospective paying customers. You might need to lash up a MVP for demonstration purposes.
BTW: Ideas are a dime a dozen. True Artists Ship ! (Steve Jobs)
Some people have become fantastically rich building products with no idea how they were going to make money. Way way way more people have gone broke doing it.
For every Zuckerberg there are a thousand homeless guys mumbling to themselves and pushing around shopping carts.