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                                            April 7, 2000

About.com, Inc.
220 E. 42nd Street, 24th Floor
New York, New York  10017

         Re:  About.com, Inc. -- Registration Statement for Offering of an
              Aggregate of 60,760 Shares of Common Stock

Dear Ladies and Gentlemen:

     We have acted as counsel to About.com, Inc, a Delaware corporation (the
"Company"), in connection with the registration on Form S-8 (the
"Registration Statement") under the Securities Act of 1933, as amended, of an
aggregate of 60,760 shares of common stock (the "Shares") and related stock
options authorized for issuance under the Sombasa Media Inc. 1999 Stock Plan
(the "Plan").

     This opinion is being furnished in accordance with the requirements of
Item 8 of Form S-8 and Item 601(b)(5)(i).

     We have reviewed the Company's charter documents and the corporate
proceedings taken by the Company in connection with the establishment of the
Plan. Based on such review, we are of the opinion that, if, as and when the
Shares have been issued and sold (and the consideration therefor received)
pursuant to the provisions of option agreements duly authorized under the
Plan and in accordance with the Registration Statement, such Shares will be
duly authorized, legally issued, fully paid and nonassessable.

     We consent to the filing of this opinion letter as Exhibit 5 to the
Registration Statement.

     This opinion letter is rendered as of the date first written above and
we disclaim any obligation to advise you of facts, circumstances, events or
developments which hereafter may be brought to our attention and which may
alter, affect or modify the opinion expressed herein. Our opinion is
expressly limited to the matters set forth above and we render no opinion,
whether by implication or otherwise, as to any other matters relating to the
Company, the Plan or the Shares.

                               Very truly yours,

                               /s/ Brobeck, Phleger & Harrison LLP
                               --------------------------------------------
                               BROBECK, PHLEGER & HARRISON LLP

