Sure you can, but then you're not strictly straight. I think men are awesome and have the utmost respect for gays and what they go through, but I couldn't ever envision myself getting head from one - I love women too much and am always thinking about them.

I'd say that if you're feeling the urge, go for it, and don't worry about being referred to as either gay or straight - it's okay to be gay and in addition, there are so many people out there who like both genders to some degree, so you're more normal than you think. I mean, just look at the percentages all over this site.