After The Deadline

http://afterthedeadline.com/
One of the best free tools that we can use to check our grammar and polish our writing is After the Deadline (AtD).  To check writing mistakes in a piece of text, paste the text inside the writing field and click the “Check Writing” button below. After processing the text, AtD will underline parts that it thinks contain mistakes. Click the underlined text to see the suggested correction(s) and/or read the explanation.

StudyDroid

https://market.android.com/details?id=com.studydroid.flashcards.free
StudyDroid is an easy-to-use flashcard application. You can get started very quickly making your own flashcards by clicking “add“. You can also make your own flashcards on your computer or you can browse the public flashcards at Studydroid to find something you like. When making your cards, it’s easy to change the text size or colour of the cards to make them more memorable.

History According to Bob

http://www.summahistorica.com/ Professor Bob Packett takes his history class and his considerable teaching experience online in the form of free history podcasts. He explains historic events from the perspective of those people who were caught up in it. He has a light style as he goes from explaining Caesar to more close events like The Korean War.

Hardcore History

http://www.dancarlin.com/
The well known podcast site by the American political commentator Dan Carlin takes an unconventional look at history with his own take on events past. Yes, you have to be in tune with his sense of humor as he rips into today’s society and relates it to historical churns. He covers topics on Roman history, the World Wars, and the Cold War to mention a few. The tag says it best – history like you have never heard before.

History On Air

http://historyonair.com/
This is a podcast blog that’s all about historical figures, events and places. The About page says that since 2005, the site has seen 3.2 million downloads of its more than 100 episodes. The site features podcasts which you can listen to first, and then go through the blog post which includes external links for more study. The study aids are helpful if you want to do more research on the event. There are videos too that are collected from around the web.

Conversion Tool

http://convert.francepropertyshop.com/
This cool looking conversion tool supports just three measurements – Length, Temperature, and Weight. But if you are looking to equalize how the Americans say it as against the British, this simple tool should do the job quickly. Put in the figure, select the unit and out pops the equivalent measurement on the other scale.

Convert World

http://www.convertworld.com/
Convertworld.com ratchets up with a few more options like wind speed conversion, absorbed dose tool, TV & monitor size converter, and a ‘language’ conversion tool, among a lot of other scientific options. You can view the converters by selecting from your choice of 28 languages.

Convert Center

http://www.convertcenter.com/
Engineering students and others too can make use of the variety of conversion options on this site. Molar mass unit conversions or frequency wavelength unit conversions will appeal to the scientifically minded. I am more interested in finding out how many gallons I can get to the liter with the fuel conversion tool.

Converticious

http://converticious.com/
The free online converter handles temperature, volume, distance, weight, area, data, time, and speed unit conversions. The interface is very user-friendly with large icons and bulleted units which you can select for your instant conversion needs.

Sooeet!

http://www.sooeet.com/
It is an offbeat name for an all-in-one unit converter. The free online tool covers all the common conversions you might use in your daily life; some purely mathematical and others (clothing size, cooking) for functional. Exchange rate calculators again are one useful tool that gives you the currency conversions with a fair degree of real time accuracy.