Getting ready for a geek birthday, or one of those holiday office parties where everyone buys a gift for someone else for less than $20? Or just shopping for a gift for your geek, and trying to find a great geek gift for less than $20? If so, you've come to the right place. I've gone through hundreds of items and found my personal favorite geek gifts for 2009 for $20 or less, and collected a baker's dozen of them right here.

I hope you like these geek gift ideas as much as I do. With the possible exception of the calendar shown below, I'd be happy to receive any of these gifts over the 2009 holiday season. (I included the calendar here because I think it will really appeal to some geeks.)

Full disclosure: I've linked to all of these products at ThinkGeek.com, but you can find many of them at other retailers as well. devdaily is now a ThinkGeek affiliate, but hey, that's a heckuva lot better than those annoying pop-under ads.

Geek gift idea - Cool Feet Laptop Airspace Stands

If you're thinking about a practical gift for your geek, and your geek has a laptop they use a lot, the 'Cool Feet Laptop Airspace Stands' look like a very good idea. While I don't have these cooling feet, I use a cooling fan under my MacBook Pro, and I highly recommend anything like this.

The Cool Feet Laptop Airspace Stands are currently $10.99 at ThinkGeek.com.

Geek gift - The ThinkGeek USB Snowbot

If your geek is into the holiday spirit, or they otherwise like fun gadgets, the The ThinkGeek USB Snowbot looks like a lot of fun. Part snowman, part robot, this USB-powered robot (just $11.99 at ThinkGeek) is sure to be a unique gift.

$20 gift ideas - USB LED Beverage Cooler

Part practical, part fun, this geek gift idea is retro-styled, and has a small blue LED light inside. I don't know how well this little guy acts as a refrigerator, but if someone gave one to me, I'd be very happy with it, and I'd sure give it a try! The USB LED Beverage Cooler is currently $19.99 at ThinkGeek.com.

Geek gift ideas - Hidden Bookshelf

The Hidden Bookshelf is one of the crazier geek gift ideas I've seen lately. You really have to look at the pictures to see how this geeky bookshelf works. If you think someone won't mind putting a few holes in the wall to mount their geeky books with a hidden shelf, this can be a very cool gift at $12.99 at ThinkGeek.

$20 geek gift idea - Barcode Doormat

If you know any geeky programmers that have been a lot of time in the barcode programming world, this Barcode Doormat may be a perfect geek gift idea for them. Either that, or it will be more torture ... one of those two, lol. Either way, nothing says 'geek' to household visitors quite like a Barcode Doormat.

The Barcode Doormat is $19.99 at ThinkGeek.com.

Geek gift idea - Mini Business Card File Cabinet

For the geek that collects business cards, this mini filing cabinet business card holder would be quite the geeky gift. It looks small, but it holds up to 800 business cards, which sounds truly amazing. The Mini Business Card File Cabinet is just $12.99 at ThinkGeek.

Geek gifts - KGB Disappearing Ink Pen

When I was younger I always loved the idea of being a spy, and having cool spy gadgets. One spy gadget I always wanted was a disappearing ink pen, and now, with the KGB Disappearing Ink Pen, I can have one. The ink Disappearing Ink Pen page on the ThinkGeek website says the ink formula was developed by the KGB during the Cold War, and it's even made in Russia, so what they heck, it sounds like a very unique geeky gift idea. (I'm probably getting this one for my brother-in-law.)

The KGB Disappearing Ink Pen is just $14.99 at ThinkGeek.com.

Geek gift idea - Despair, Inc. 2010 Custom Calendar

I wouldn't be a particular fan of this next gift idea, but I know many programmers who would like it. Here I'm talking about the 'Despair, Inc. 2010 Custom Calendar'. This calendar comes with special "de-motivator" designs each month, and marks of noteworthy geek dates.

This most unique calendar is just $15.99 at ThinkGeek.

$20 gift ideas - #include glasses

If your geek is a beer drinker (and C/C++ programmer), the "#include " beer glasses might be just the right gift. Okay, they don't even have to be a C/C++ programmer to enjoy these, but it will help them understand the "include" reference. Prices vary from $5.99 to $19.99.

$20 geek gifts - LED Binary Clock

I've written about the LED Binary Clock here before, so I won't add too much to it here, other than to say that it screams 'geek gift', and I mean that in a good way. After all, who else would own a Binary Clock but a geek?

The LED Binary clock is currently $19.99 at ThinkGeek.com.

Geek gift idea - USB LED Christmas Lights

If your geek is into the Christmas/holiday spirit, these USB LED Christmas Lights might be a great idea. Powered by a USB port on their computer, your geek can enjoy the glow of red and green lights that traditionally reminds us all of this great time of year.

The USB LED Christmas Lights are currently $13.99 at ThinkGeek.com.

$20 geek gift idea - DIY Dinosaur Lamps

I just saw these 'DIY Dinosaur Lamps' today, and while they aren't something I'd personally be interested, they might be a great gift idea for anyone that grew up loving dinosaurs or the Jurassic Park movies. They require a little construction, but for the dinosaur-loving geek, these 'DIY Dinosaur Lamps' ($19.99 at ThinkGeek) might be a lot of fun.

Geek gift - USB Plasma Ball

You wouldn't hurt my feelings by buying me a 'USB Plasma Ball'. I'd enjoy seeing this Plasma Ball next to my laptop or PC. Admittedly, this geek gift idea has almost absolutely no practical value, but it would be fun geek toy. :)

The USB Plasma Ball is currently $12.99 at ThinkGeek.com.

My "geek gift ideas" collection

As I wrap up my series of geek gift ideas for the 2009 holiday season, here's a link to the articles I've written over the last few days:

• Geek gift ideas for under $10
• Geek gifts for under $50
• Geek gifts for under $100
• Geek gifts for under $1,000