Gift for Bride and Groom when you're the Best Man?

[BigRedBeta]

I'll be the Best Man for one of my HS friends (he's an only child) for his wedding in May (I want to make sure that I'm prepared). Even though I went away for college, we've remained close, and I've become almost equally as close with the bride (their actually #2 and #3 in my speed dial) over the course of the last 6 years they've been dating, since the fall of our freshman years. I'm super pumped for this, even started writing my toasts, and I want to make sure I've got everything covered. I've read a number of websites and have seen that other than the bachelor party, I'm expected help with the tipping of wait staff and DJ's, the officiant's fee, drive the couple to the airport if they're leaving the next day, arrange for flowers in their hotel room etc. But I haven't seen anything about getting gifts.

So...what's acceptable? What's creative or unique?

I thought about getting them a nice bottle of champagne - Dom or an equivalent (they do drink, so that's not an issue...lord do they drink), that they might be able to share on their 1st anniversary, but didn't know if there was something more traditional or more accepted as the standard.