Be careful with WellsTrade/PMA as they will be changing the terms. I believe (but have not read an WF announcement) that come April, they will no longer do the free trade stuff, but everyone before that will be grandfathered in. The minimum is now $50,000 and not $25,000. See
Bogleheads • View topic - WellsTrade Changing Its Tune?
WellsTrade/PMA - 100 free trades per account per year including no commissions on many (but not all) Vanguard mutual funds
Vanguard - free trades on Vanguard mutual funds and Vanguard ETFs. You do not need $1million to get these free trades. You do have to have a heartbeat though.
TDAmeritrade - free trades if you sign up and follow the restrictions on about 100 ETFs including the most popular Vanguard ETFs
Fidelity - free ETF trades on about 30 iShares ETFs. Fidelity also lowered the minimums on their Spartan Index funds.
Schwab - free ETF trades on Schwab ETFs
MerrillLynch Edge/BoA - free trades if you keep lots of cash with them
Scottrade - I think they have some free trades, too.
Several brokers are giving cash bonuses or other deal to open new accounts and/or send new money to them.
Basically, if one is paying a commission nowadays, they are paying too much.