Link it in to sat-nav systems and it could be very interesting. Also, to counter xirium's (perfectly reasonable) point about companies being reluctant to share information: if you sell it to one parking company, then customers will know which of that company's car parks to go to, which is an efficiency benefit for them. If they're doing it, other companies might feel they have to as well.

The entry barrier is higher than the average YC startup (and the like) for this idea. It isn't a pure software solution, content requires cooperation/contracts among parking lot owners, as well as the distribution method (I doubt you would do it for cellphones because satnavs will be a vastly superior tool for thus).

Knowing a friend who is a real-estate agent who tried for months (unsuccessfully) to negotiate the purchase of a single building that was owned by one of the mega-huge global-local parking lot conglomerates for a rich client, the barrier to entry is connections to metropolitan parking lot enterprise(s)

Might work as an iPhone or mobile app. Not as an app for standard browsers -- the data are too time-sensitive, and I don't have the coordination to juggle a laptop while driving a car.

What I'd really kill for is a version of this app that could alert me to on-street spaces, or other cheap alternatives. I don't usually have much trouble parking in downtown garages -- they cost so much that they often have spaces, and if they don't have spaces they generally have signs at the entrance to tell you. I once had the bright idea of planting a sort of super-RFID in the pavement under each on-street parking space -- or maybe in the parking meters? -- and monitoring those with an online service. Make that work and I'll be your friend for life.

No need: Grab satellite images; Parse the spots for availability; Produce a "Heat Map". Done.

Well, someone has already poked a hole in the "satellite images" idea -- not updated enough.

OTOH, let me attempt to rescue your excellent idea with this suggestion: cameras mounted on nearby buildings? Cameras are getting really cheap!

That'd actually be pretty cool. Might have some privacy issues with it though?

How many satellite images are updated with real-time frequency? Likely answer: none.

I could see this turning into a tool that allows parking garages to sell spaces in advanced. If I'm already downtown it's unlikely that I'm going to think to pull up my phone to find a spot that will probably get taken before I get there. (I would be more likely to use a satnav system to find a parking spot, but the problem of the spot being taken in the meantime still exists).

Using the same technology, but for parking garages to sell in advanced (think fandango or stub hub for parking) would eliminate the only remaining issue.

You could even use an auction format for the prices (garages will like this) so that when parking for major events is sold, the prices reflect the demand for the spaces.

Parking companies are unlikely to share information if it disuades customers from speculatively finding a space. However, if you allow advance booking via mobile telephone then the parking company obtains revenue even if you don't use the service.

Asking people to use Google Maps on their mobile device while driving is a terrible idea. You're going to get sued by everybody who runs over a pedestrian or a mailbox while using your service, which will be just about everybody.

I was trying to use Google Map's "Directions" feature on the iPhone in NYC (yes, I was driving and was on the wrong side of Manhattan, lost) and it never worked - "Service unavailable". Google Maps - search for ___location worked however. Almost had to resort to last-ditch call my brother-in-law "Onstar" style service but I managed to get where I was going.

This is actually a future component of my project http://www.propertystampede.com. We are initially focusing on property managers, but then later to parking lot managers. Our goal is to create a site where someone is relocating for work to a new city, can login, pick an apartment, apply online, then find parking near their new place of employment and purchase a monthly parking pass...

What do you guys think?

How would you check your mobile phone for parking spaces if you aren't parked? I guess you could have a passenger do it, but that's not always possible.

Great idea. How about a SMS gateway where you could text your ZIP code and it would return a list of garages and number of open spaces. this would be a lot easier than typing in a web address, and would be quick enough for you to do it at a stop light.

Also, I know some people that work at a company that makes the software for said garages.. I could talk to him / connect you two.

Mail me: valor _at _schnooze _dot _com

We are doing something very similar to this.

http://www.parkonthefly.com/

Email me: [email protected]

The service isn't live yet.

An interesting feature is the ability of private people to sell the use of their parking spaces while they're not using them. Very interesting.

I was going to post spotscout.com but it does prove that when you think of it...10 other people are building it!

its a good idea - u can either make mobile app or on gps navigator or even with GM OnStar service ... one can also make an app to send automatic sms text message on your cell phone.