Given the state of the economy, and the potential of a rough near future for us recent grads (i.e. on/off work), I would recommend holding off on large purchases while your life is in flux. This includes both a NEW car and purchasing a house.
My short answer is: you need a reliable vehicle, so purchase a used car, from a major dealer (yes this will add a fairly high premium, but easier financing), that is 4-5 years old, or more. Barring the major dealer purchase, be sure to get a mechanic to check out a vehicle, many will offer this service for a reasonable payment. As people point out, cars these days will run for another 100k miles. You will NOT have to pay anywhere near $27,000 for this vehicle. You may need to leverage your 10k for a loan if you choose to finance, but it should not be a problem, especially as you seem to imply an established credit history.
In addition to this, start saving your money for the house you would like to eventually get. We have no idea where you live, but, picking rough numbers, assuming a 2 year buy period, 20% down, and a $250,000 home, the down payment alone will require you to save ~$2,000/month starting now.
Barring either of these options, max out your money to tax sheltered accounts (your Roth IRA, work 401k, or a regular IRA) asap. Obviously, do not deplete your emergency fund, if anything, increase it. 10k can be burned through in a heartbeat.
Long Answer: I purchased a brand new car, right out of school, at a reasonable interest rate. Like you, I can afford this vehicle, however, if someone were to come to me today (3.5 years later) and offer me the opportunity to take it back and purchase a 4-5 year used vehicle, at a 4-5 year used car price, albeit at a much higher interest rate (since I financed), it would be about a 0.02 second decision.
I like my car, but, I'd like the differential cash savings between it and a reliable used car more. $27,000 is also fairly expensive for a new vehicle, there are many, very nice vehicles, for 21-23k. I still would not consider these priced appropriate to spend your money on them, but they exist. However, you do very much need a reliable vehicle, and I think you should get one.
On the home front, your $400 all inclusive rent is insanely cheap. Many people spend more than that on property tax and PMI each year, so anyone who throws the "You're throwing money away!" line at you is blowing smoke to justify their own home purchase. Take the money you would have spent on a mortgage, and squirrel it away. Do your own due diligence and research the home market in your area and decide for yourself if you think home prices have bottomed and will stay there, have further to go, or are going to begin to rise. That is a decision only you can make for yourself.
I'd add a section about getting expenses under control, but you said you could save 50% of your takehome pay. This is an order of magnitude above the average. Good job. Try doing 50% for 4 months, then calculate your actual amount. Then try to beat it.