IMHO - It makes a great second job/hobby, assuming you are not independently wealthy or were not born into a family of studio execs, producers, directors, etc. If you have success in selling your work & develop a good rep or get hired by a studio , then consider giving up your day job.

I wrote all of this and then lost it - so let's have another go! Firstly - if you want to be a screenwriter, try not to think 'Hollywood' right away. Yes, Hollywood exists, box office numbers are huge - lots and lots of money is made. But you can't just dive right into deep end. My main piece of advice: LEARN ABOUT PRODUCTION! Learn about filmmaking in its entirity - don't just become engulfed in writing. You have to know the ins and outs of the medium for which you wish to write. And this gives you bonus points. Your first target is producers - so if you know their job inside out, you'll know what they look for, and more importantly, what they don't. Start small and think low-budget! Build up a portfolio of strong 5 to 10 minute scripts - develop them. Watch short films, go to festivals - build relationships with producers and directors. Look at it this way - the smaller the budget to get your film made - the more likely a producer will give you a chance. There's less risk involved with short films. This is how you establish good working relatinships in the industry. But maintain your protfolio! Remember - you can still do all of this alongside your day job - just be relentless, passionate and determined. If this is really what you want and what you're good at - you will stick with it. Expect rejection - it is a huge part of the job. In short - I guess my answer is yes - you can be a screenwriter, but it takes a huge amount of dedication, and it takes time. I'm 26, I'm dyslexic, but I graduated a media production degree in 2008 - I won the university award for best screenplay - I now work as an in-house copy screenwriter for a corporate production company - and as a freelancer, I have just been awarded my first commission by the UK Film Council for a short, low-budget film. I'm only one rung up, on a very long ladder! But I guess the view at the top will be worth the journey! Good Luck!