I'm currently considering a coworking space for occasional needs. Sometimes more, sometimes less. Actually, it's all driven by the cost. If I'd be lucky enough to find something similar to Mountain View's Hacker Dojo I would go with it right away. Anyways, here is what I've found so far:
Office & Company in Pasadena, CA. The closest location to my place, and probably the cheapest one. They do have drop-in rate for $25 a day, with full membership price of $350/month. If they would provide a half day for $10 or close, I'd go with them by no means.
CoLoft in Santa Monica, CA. One of the newest, I guess, and pretty interesting. The cheapest plan is 5 hours a month for $30, which is sorta okay, but still doesn't look to be within the budget. Spending 4 days a week, at least 3-4 hours a day, can end up with about 64 hours a month, and the lowest closet plan is 50 hours a month for $199. Ouch.
theOffice in Santa Monica, CA. They provide an intro rate of $149 for month and then it goes up. The limited amount of guest passes is $39 per day. I've heard that they are pretty cool, but they're rather expensive.
And finally Blankspaces in Los Angeles, CA. They are the most expensive, from what I was about to understand. However, the day rate working out of the work bar for 5 hours is only $20. Which is pretty cool.
That's all I found so far. Which is not a lot, but still an option. I'll keep an eye on the new places. And while I'd prefer beach area :) I'll be probably do fine with the central LA.