Most of us probably use an online broker like E*Trade Financial (ETFC)TD Ameritrade (AMTD), or Interactive Brokers (IBKR 1.31%) to buy and sell the shares of companies in which we invest, but what about using our broker to buy shares of, well, brokers? Let's take a look at a few industry leaders.

So easy, a baby can do it
Perhaps best known for its financially savvy talking baby, E*Trade Financial is a pioneer of online trading. Though the baby recently quit (or was he fired!?), this hasn't held E*Trade back. Recently, the company released better-than-expected results for its first quarter with a 13% increase in net revenue. E*Trade's $475 million in revenue beat the consensus estimate of $455 million, and Wells Fargo recently upgraded E*Trade from "market perform" to "outperform."

However, FINRA is currently investigating E*Trade's order routing practices, questioning whether customers are getting the best prices when they place trades. The news has dragged shares of E*Trade down a bit as of late, which has caused many to sit on the sidelines and keep an eye on this stock until the matter is sorted out.

The importance of good acquisitions
Over the years, through a series of acquisitions TD Ameritrade has become a powerhouse in the online-brokerage space. Like E*Trade, Ameritrade too posted positive figures for its most recent quarter, with revenues up 34.7% from the same quarter last year. Net revenue came in at $812 million, which beat the consensus estimate of $786 million.

Aside from the numbers, TD Ameritrade has made lots of headway in providing its customers with great trading tools, such as its 2009 acquisition of the Thinkorswim trading platform. The company is set to debut Thinkorswim Sharing, which will allow users to securely share customized settings for charts, workspaces, market scans, and other features with other users.

The new feature is an industry first that will allow Thinkorswim users to analyze each other's strategies, which will possibly lead to better market insights and more winning trades. It may bring new customers and more revenue from commissions to Ameritrade as well.

Routing options
This has been a good year for Interactive Brokers, with its daily average revenue trades rising 20% over the prior year. The company has also taken steps to distance itself from order-routing concerns like those dragging E*Trade down. In April, Interactive Brokers announced that it would become the first online broker to offer direct access to IEX, the upstart stock-trading venue featured in Michael Lewis' book, Flash Boys: A Wall Street Revolt. Interactive Brokers' customers can also use IB SmartRouting technology, which searches for the best prices available when a customer places an order.

Bottom line
Brokers aren't just for placing your trades, their shares can add some value to your portfolio as well. Regardless of which broker you use to place your trades, shares of any one of these three brokers could add a nice boost to your portfolio.