Is it bad business etiquette to email someone after 5 PM if you're seeking employment?

I may be naive, but I can't see why it would matter what time you emailed a resume to an employer.

It's up to them, if they're a workaholic and can't take their Blackberry out of their hands for a minute, if they would reply at 12 midnight.

Now phoning, that would be a whole different thing.

Email whenever you like; they will answer when they are available.

I agree - it doesn't matter what time of day you email - as they will read it when they a chance - whether it be 6pm or 6am.

Exactly.
If you looking for employment, you may not be able to email from the job you're at during the day.
The potential employer will know you're emailing on your own time.

Correct re phone calls.

I get people returning my calls, leaving me VM's at 7pm or after, like they seem surprised I'm not there.
I don't mind when they leave a message saying they are acknowledging my call, and will call back in the morning, although that's useless and a waste of time IMO. The one's who leave a message, especially on a Sunday afternoon, like they thought I would be there, are really annoying.

I think it's more appropriate to wait and email these people when their businesses are open. These people do not know you.

What difference does it make when you email them?

They aren't going to open your email until they are at work themselves. You are going to send your resume to their work address, not their personal email.

what if you are working, and can't email them while you are at your job?

What difference does it make if they know you are not?
I get emails from people at work and before I open them I notice they sent it to me at 5am, or 10 or 11pm.
What do I care, I didn't decide to open it until 9 or 10am

You can choose as you wish. I hire and interview people all the time in a professional environment. Email timing would not impact me one way or another. Usually one doesn't even note the time of the email unless you have some sort of policy of answering within so many hours.

Like Chai said though - a phone call even a voice mail would seem inappropriate in most circumstances at non-business hours.

One thing you did note too that could actually work as a positive - is that you are sending an email after hours when you are currently working. Shows that you have concern about working during working hours.

Many workplaces now also have extensive on-line application processes. I actually just did one last night myself. HR probably comes in and has a slew of applications from overnight.

Plus, what happens when they get applications from people who are outside of the time zone?

Yeah.

I did an application last week, and sent it the next day after looking it over, at 7am.

I think if there's a general employment inquiry you want to ask someone, an email is no big deal.