Google Adsense The Easiest Money

Google Says
Your earnings for referrals will vary depending on the product you're referring.

For non-Google products, each individual advertiser decides the actions they'd like users to complete on their site and how much they're willing to pay for those actions. You can view the amount of this payment displayed on the product details page for each product. For every action the advertiser has defined, you'll see your potential earnings listed in the Payment column.
You'll be credited for non-Google referrals if a user who clicked on your ad completes the advertiser's conversion criteria within 30 days of clicking.
For Google products, your earnings will be determined as listed below.

AdSense:
When a publisher who signed up for Google AdSense through your referral first earns US$5 within 180 days of sign-up, you will be credited with US$5.
When that same publisher earns US$100 within 180 days of sign-up and is eligible for payout, you will be credited with an additional US$250.
If in any 180-day period you refer 25 publishers who each earn more than US$100 within 180 days of their respective sign-ups and are all eligible for payout, you will be awarded a US$2,000 bonus (bonus payouts are limited to 1 per year).
Firefox plus Google Toolbar: When a user you've referred to Firefox plus Google Toolbar runs Firefox for the first time, you'll receive up to US$1 in your account, depending on the user's location. Your referral must be a Windows user, who has not previously installed Firefox, in order for you to receive credit.
There are 100's of other referral products provided by Google.

AdWords:
When an advertiser you refer first spends US$5 within 90 days of sign-up (in addition to the US$5 sign-up fee) you will be credited with US$5.
When that same advertiser spends US$100 within 90 days of sign-up, you will be credited with an additional US$40.
If in any 180 day period you refer 20 advertisers who each spend more than US$100 within 90 days of their respective sign-ups, you will be awarded a US$600 bonus (bonus payouts are limited to 1 per year).
Pack: When a Windows user you've referred to Pack downloads and installs the product, you'll receive up to US$2 in your account.
Checkout: When a user signs up as a buyer and completes a transaction through Google Checkout of at least US$10 (before tax and shipping) within 90 days of sign-up, you will be credited with US$1.
Google Apps: When a user signs up for Google Apps and there are one or more Google Apps email accounts in use for four consecutive weeks, you will be credited with US$5.
You can track your earnings from referrals by visiting your Overview page, where we'll display earnings separately for each product.
Monthly totals of referral credits will appear on your Payment History page - just click the Earnings detail for any month to view specifics about how much you've earned through referrals. Your earnings from referrals will be included with your earnings from AdSense for content and AdSense for search.