From the September 2010 issue of Entrepreneur

If you're self-employed and pay quarterly estimated taxes, the IRS is likely looking for some cash from you by Sept. 15. These websites won't take away the pain of the payment, but they'll make it a bit easier to settle up with Uncle Sam.

Shoeboxed.com
What it does: Mail receipts or take photos with your phone and the company scans or organizes the images for you.

How it helps: Eliminates the tedious process of copying and organizing the receipts you need when calculating your tax returns.

Cost: The first month is free, then monthly fees range from $9.95 to $49.95.

About.com Tax Planning
What it does: Offers an excellent primer on calculating quarterly taxes, among other benefits.

How it helps: With clear explanations and links to the forms you need, the site is a terrific resource for all things tax-related.

Cost: Free

Paycycle.com
What it does: This Intuit site lets you perform a multitude of payroll functions, from issuing checks to filing returns.

How it helps: When you use the site to issue your personal payroll checks, your information is stored there, which makes filing your quarterly returns a breeze.

Cost: The first month is free, then you pay based on the size of your firm, number of contractors and number of states in which you file.

IRS.gov
What it does: The agency's eFile system, which you can find on the homepage, lets you file many returns online. Enrolling in the Electronic Federal Tax Payment System allows you to also make payments online.

How it helps: No stamps, no post office lines. Just log on, choose one of the IRS payment partners from the list, enter your info and you're done. The catch is that you'll be working with an outside provider and paying a fee.

Cost: Depends. Partner esmartpayroll.com charges $4.95 for one 941 form, while esmarttax.com is a subscription model--after a free trial, the cost ranges from $9.95 to $149 per year with additional fees for state returns.