1. A method of providing a computer-implemented trading platform for intercepting trades, coordinating trading or preventing offsetting trades of one or more financial objects, the method being executed on a data processing system, the method comprising: providing, receiving or accessing by at least one computer taxation rules; determining by the at least one computer if a trade using said selected lot should be deferred using a computer database and said taxation rules; generating by the at least one computer a deferred trade in a tax-managed sub-account if it is determined that said requested trade should be deferred; selecting by the at least one computer said deferred trade in said tax-managed sub-account for execution if it is determined that said deferred trade should no longer be deferred using said computer database and said taxation rules; managing a virtual portfolio of the financial objects by the at least one computer, wherein said virtual portfolio comprises a collection of the financial objects managed collectively but tracked separately with separately owned lots on behalf of a plurality of investors, wherein the financial object comprises at least one of: equity, debt, a bond, a stock, a financial instrument, a contract, a security, a derivative contract, a mutual fund, an exchange traded fund (ETF), a fund of funds, an index fund, a passive index fund, an enhanced index fund, an actively managed fund, a non-capitalization weighted index fund, a capitalization weighted index fund, an equal weighted indexed fund, an international fund, a sector fund, an asset, a liability, an accounting data based index (ADBI) fund, a portfolio of assets, a portfolio of assets tracking an index, a portfolio of assets tracking at least one of S&P indexes, FTSE indexes, Russell indexes, Dow Jones indexes, Morgan Stanley indexes, Lehman indexes, Wilshire indexes, composite indexes, international indexes, or Morgan Stanley Capital International indexes, a portfolio of assets tracking an ADBI weighted index, a commodity, an option, a derivative trade, a long hedge, a short hedge, a swap, a futures contract, or a hedge fund; providing, receiving or accessing the at least one computer database associating a plurality of lots owned by each of said plurality of investors and associating by the at least one computer said plurality of lots as tradable regardless of an initiator of the purchase of said plurality of lots; providing, receiving or accessing lot selection rules comprising investment management rules comprising at least one of: coordinating trades, enforcing compliance with policy, or preventing offsetting trades comprising avoiding both purchasing and selling the same lot; receiving by the at least one computer, a requested trade; and selecting by the at least one computer, a lot for trading from said plurality of lots using said computer database, said lot selection rules, and said requested trade.