This is one of my house's biggest windows, which faces toward the street (you can see the street in the reflection):
I wanted to put up something festive and wintery, without a particular religious bent, so anybody looking at the window could find something they liked to see.
So I came up with snowflakes and stars--some with five points, some six, and some even eight.
This is the Big Kahuna snowflake, below--purchased full price at a beautiful local boutique. At $15 a pop, however, this is an expensive way to decorate!
So I mixed in some ridiculously cheap stars and snowflakes that I made out of scraps of this and that lying around. I made some stars out of cardboard covered with aluminum foil:
Some I made out of stiff, glossy white paper, crudely decorated with glue and glitter:
And also popsicle-stick stars, spray-painted white, hot-glued together, and decorated with glitter:
In betweeen the high-end and low-end decorations are these smaller snowflakes of beads and glass and plastic, which I picked up for about $2 or $3 each, at post-holiday sales:
I put up one or two stars and snowflakes per window pane, with room to spare. After the holidays, I'll probably buy some more half-price snowflakes and such, to add in next year.
You could adapt this idea and use tree ornaments, decorated cookies, even oversize letters to spell out a seasonal message (imagine across the four panes of windows "Peace," "Love," "Joy," and "Family"). High-, medium-, or low-end, the effect is terrific!