Lots of people are incredibly busy and can't get to any special Advent worship, studies, prayer times etc.

Here are some possibilities that take only a few moments, and can be done at a time to suit you...

The Northumbria Community have some podcasts here

GRF Christian Radio have audio shorts here (you have to register to listen/download but it's free; type advent into the keyword search and off you go)

There is the emerging church prayer lava lamp here, just follow the instructions

And, pinching an idea from someone else, I have set up a 'group' candle stand at gratefulness.org here.  Simply click on the 'light a candle' link on the left side of the screen.  Then click the search menu at the top of the page, type PIA (Pause in Advent) in the group search box and it will take you there.  Then just follow the instructions.  I suggest that you avoid any full names, using first names, pseudnyms or initials only if you want to pray for people, and that you mask your own identity too.  This is all free, and you don't have to add any details - I won't know who visits.  The 'candles' last for 48 hours, if they all burn out the stand vanishes, but can easily be re-made simply by lighting a candle from the general candle page.

So, four possibilities, from under a minute to about fifteen ... hopefully something will work for you.