sample.ledger:

2007/01/01 income
    assets:checking  $1
    income:salary

2007/01/01 gift
    assets:checking  $1
    income:gifts

2007/01/01 save
    assets:saving  $1
    assets:checking

2007/01/01 * eat & shop
    expenses:food      $1
    expenses:supplies  $1
    assets:cash

2008/1/1 * pay off
    liabilities:debts  $1
    assets:checking

Sets up this account tree:

Account top with 0 transactions
+- Account assets with 0 transactions
|  +- Account assets:cash with 1 transactions
|  +- Account assets:checking with 4 transactions
|  `- Account assets:saving with 1 transactions
+- Account expenses with 0 transactions
|  +- Account expenses:food with 1 transactions
|  `- Account expenses:supplies with 1 transactions
+- Account income with 0 transactions
|  +- Account income:gifts with 1 transactions
|  `- Account income:salary with 1 transactions
`- Account liabilities with 0 transactions
   `- Account liabilities:debts with 1 transactions

ledger 2.6 balance reports:

$ ledger -f sample.ledger -s bal
                 $-1  assets
                 $-2    cash
                  $1    saving
                  $2  expenses
                  $1    food
                  $1    supplies
                 $-2  income
                 $-1    gifts
                 $-1    salary
                  $1  liabilities:debts

$ ledger -f sample.ledger bal o
                  $1  expenses:food
                 $-2  income
--------------------
                 $-1

$ ledger -f sample.ledger bal a
                 $-1  assets
                 $-2    cash
                  $1    saving
                 $-1  income:salary
                  $1  liabilities
--------------------
                 $-1

$ ledger -f sample.ledger bal e
                 $-1  assets
                  $2  expenses
                  $1    supplies
                 $-2  income
                  $1  liabilities:debts

$ ledger -f sample.ledger bal i
                  $1  assets:saving
                  $1  expenses:supplies
                 $-2  income
                 $-1    gifts
                  $1  liabilities
--------------------
                  $1

$ ledger -f sample.ledger bal u
                  $1  expenses:supplies
--------------------
                  $1