Search exactly what you want!!!

1. Explicit Phrase: Let’s say you are looking for content about mobile phones. Instead of just typing mobile phones into the Google search box, you will likely be better off searching explicitly for the phrase. To do this, simply enclose the search phrase within double quotes. Example: “mobile phones”

2. Exclude Words: Let’s say you want to search for content about mobile phones, but you want to exclude any results that contain the term old. To do this, simply use the “-“ sign in front of the word you want to exclude.
Example Search: mobile phones -old

3. Site Specific Search: Often, you want to search a specific website for content that matches a certain phrase. Even if the site doesn’t support a built-in search feature, you can use Google to search the site for your term. Simply use the “site:anysite.com” modifier. Example: “mobile phones” site:www.nokia.com

4. Similar Words and Synonyms: Let’s say you are want to include a word in your search, but want to include results that contain similar words or synonyms. To do this, use the “~” in front of the word. Example: “mobile phones” ~personal

5. Specific Document Types: If you’re looking to find results that are of a specific type, you can use the modifier “filetype:”. For example, you might want to find only PowerPoint presentations related to internet marketing. Example: “mobile phones” filetype:pdf

6. This OR That: By default, when you do a search, Google will include all the terms specified in the search. If you are looking for any one of one or more terms to match, then you can use the OR operator. (Note: The OR has to be capitalized). Example: mobile phones OR laptops

7. Phone Listing: Let’s say someone calls you on your mobile number and you don’t know how it is. If all you have is a phone number, you can look it up on Google using the phonebook feature. Example: phonebook:07543-2456567

8. Addresses. Type in any address into Google, including the city and state and Google will provide a map of the area, as well as the ability to get directions to the location. Example: 223, kolha market, kolkata, india

9. Stock (Ticker Symbol): Just enter a valid ticker symbol as your search term and Google will give you the current financials and a quick thumb-nail chart for the stock. Example: GOOG

10. Calculator: The next time you need to do a quick calculation, instead of bringing up the Calculator applet, you can just type your expression in to Google.
Example: 235*123456

11. Word Definitions: If you need to quickly look up the definition of a word or phrase, simply use the “define:” command. Example: define:augmentation

Google Voice

Google is always innovative and customer friendly. From a wide variety of creative product to the technology equipped gmail, orkut, youtube or what not. Now it is google voice Google Voice or like Google Number is the latest thing in Google's pocket. Using this you can actually make calls, send voice mails, convert voice to text or can use a single phone number while switching the services.
The technology is available only for US people for now but they say they will soon be launching it to india too. More information about google voice can be obtained here.