"Hey, quick question."
I've found that this phrase has become the preface for the majority of questions at work. If you can't answer the question yourself, how can you determine if it's always going to be quick to answer? I know I've asked questions I thought were quick, when in fact a long discussion unfolded, and vice versa.
Yes, there are instances when this phrase applies. It's alright to use, just not every time you pose a question. Furthermore, the more you use it the less people will pay attention to it because it will slowly lose its meaning.
After a while, it can even start to come across as an apology. Why would you apologize every time you had to ask a colleague a question? We're all paid to be at work and solve problems, most of which take some degree of brainstorming, collaboration, and information gathering. There's no need to feel guilty about asking a question of your colleague unless it's the 10th time this week you've asked the same thing or you can't manage to get anything done without some hand holding.
If you're still feeling awkward about it, here are some alternatives you can use. A variation of one I picked up from Laura Steck & Jean Hollands is:
"Are you interruptable right now?"
Try it every now and then. When a person hears this, it says to them that you understand you are interrupting and acknowledge that you're taking them away from what they're currently doing. If they really can't take the time it also gives them an easy way to say something like "Well, I'm a little busy right now; can you come back/call in about...?"
"May I bug you about...?"
It's a little playful without being too syrupy-sweet.
"Do you have a few minutes?"
Notice I didn't ask if they have a second, or a minute; I tried to make it more realistic, so if later on I really just need them for a quick bit, they might believe me more readily!
"Question for you...."
Sometimes just politely stating you have a question and asking it is fine. Once again, the person can decide if they have time to address it with you in the moment, or let you know if they'll need more time.
"Can I ask you a question?"
I myself am a smarta*s and usually answer with, "You just did. Did you have another question you wished to ask?"
The Bottom Line:
Please, just ask the question! For the most part, if people are busy, they usually will ask that you come back/call later, email them, etc.