If you've been wanting to purchase a good quality bluetooth wireless speaker to pair up with your Nexus 7 then there's a great deal going on right now. Amazon and Philips have two great models on huge discount right now. The first, the Philips Shoqbox Wireless Portable Bluetooth Speaker with Built-In Mic SB7260/37 (Purple) gets rave reviews and it's 75% off at only $49.99 (usually $199.99). The model on sale is in purple which really looks sharp but it's also available in three other colors. You can even pair two of them together to create a left and right stereo wireless soundfield powerhouse. Pretty sweet. It's built like a tank too and is weather resistant so you can take it outside, even splash it with water and it'll keep pumping out the tunes. Even has a built-in mic so you can use it as a speakerphone.
If you want something a little smaller they also have the Philips SBT30/27 SoundShooter Wireless Portable Bluetooth Speaker for only $24.99 (50% off). This thing is really cool...it looks kinda like a little hand grenade but the only thing exploding out of it is sound. It's available in a variety of colors including black, blue, green, orange and more. It also has a built-in mic for hands free calls. Just toss one of these things in your backpack or bag and you'll have a great portable speaker that gets over 8 hours of battery life on a charge. And for only 25 bucks? It's a no brainer.
I should add that Philips makes quality stuff. The speaker sound quality and bass response is fantastic. This is not a cheap no name brand that sounds like junk. This is the real deal. Grab one or two while they got em at these prices.