An SAP Consultant

 Selection-screen 
RS_COVERPAGE_SELECTIONS Returns an internal table that contains a formatted list of all the selection parameters entered for a report. Table is ready to print out.

RS_REFRESH_FROM_SELECTOPTIONS Get the current contents of selection screen

RS_VARIANT_CONTENTS - Returns the contents of the specified variant in a table.

F4IF_SHLP_EXIT_EXAMPLE documents the different reasons to use a search help exit, and shows how it is done.

FILENAME_GET popup to get a filename from a user, returns blank filename if user selects cancel

F4IF_SHLP_EXIT_EXAMPLE documents the different reasons to use a search help exit, and shows how it is done.

F4_DATE - displays a calendar in a popup window and allows user to choose a date, or it can be displayed read only.

F4_IF_FIELD_VALUE_REQUEST Use values from a DDIC table to provide a list of possible values. TABNAME and FIELDNAME are required fields, and when

MULTIPLE_CHOICE is selected, more than one value can be returned.

HELP_START Display help for a field. Useful for doing AT SELECTION SCREEN ON VALUE REQUEST for those fields that do not provide F4 help at the DDIC level.

F4IF_INT_TABLE_VALUE_REQUEST F4 help that returns the values selected in an internal table. Very handy when programming your very own F4 help for a field.

HELP_VALUES_GET_WITH_TABLE Show a list of possible values for F4 popup help on selection screens. This function module pops up a screen that is just like all the other F4 helps, so it looks like the rest of the SAP system. Very useful for providing dropdowns on fields that do not have them predefined.

Example:
tables: t001w.
DATA: lc_werks      LIKE t001w-werks,
ltab_fields LIKE help_value OCCURS 0 with header line,

BEGIN OF ltab_values OCCURS 0,
feld(40) TYPE c,
END OF ltab_values.

*-- Set up fields to retrieve data
ltab_fields-tabname    = 'T001W'.
ltab_fields-fieldname  = 'WERKS'.

ltab_fields-selectflag = 'X'.
APPEND ltab_fields.

ltab_fields-tabname    = 'T001W'.
ltab_fields-fieldname  = 'NAME1'.
ltab_fields-selectflag = space.
APPEND ltab_fields.

*-- Fill values
select * from t001w.
ltab_values-feld = t001w-werks.
append ltab_values.
ltab_values-feld = t001w-name1.
append ltab_values.
endselect.

CALL FUNCTION 'HELP_VALUES_GET_WITH_TABLE'
EXPORTING
fieldname                 = 'WERKS'

tabname                   = 'T001W'
title_in_values_list      = 'Select a value'
IMPORTING
select_value              = lc_werks
TABLES
fields                    = ltab_fields
valuetab                  = ltab_values
EXCEPTIONS
field_not_in_ddic         = 01
more_then_one_selectfield = 02
no_selectfield            = 03.
Exporting lists 
LIST_TO_ASCII - convert an ABAP report (displayed on screen) from OTF to ASCII format
WRITE_LIST - Useful for writing out the list contents that result from the function LIST_FROM_MEMORY.
WWW_LIST_TO_HTML - After running a report, call this function to convert the list output to HTML.
LIST_TO_ASCII - convert an ABAP report (displayed on screen) from OTF to ASCII format
LIST_FROM_MEMORY - Retrieves the output of a report from memory when the report was executed using SUBMIT... EXPORTING LIST TO MEMORY. See also WRITE_LIST.
Dynpros
DYNP_VALUES_UPDATE - Similar to DYNP_VALUES_READ, this function will allow the updating of fields on a dynpro. Very useful when you want to change a field based on the value entered for another field.
DYNP_VALUES_READ - Read the values from a dynpro. This funciton can be used to read the values from a report's selection screen too.
SCROLLING_IN_TABLE - If you are coding a module pool and using a table-control, you can use this function SCROLLING_IN_TABLE to handle any scrolling.
RPY_DYNPRO_READ Read dynpro, including screen flow  
Other 
RZL_SLEEP - Hang the current application from 1 to 5 seconds.
RZL_SUBMIT - Submit a remote report.
SAPGUI_PROGRESS_INDICATOR - Display a progress bar on the SAP GUI, and give the user some idea of what is happening
COMMIT_TEXT - To load long text into SAP
G_SET_GET_ALL_VALUES - Fetch values from a set.
HR_DISPLAY_BASIC_LIST - is an HR function, but can be used for any data. You pass it data, and column headers, and it provides a table control with the ability to manipulate the data, and send it to Word or Excel.
GET_GLOBAL_SYMBOLS Returns a list of all tables, select options, texts, etc for a program. Even includes the text definitions for the selection screen
GET_INCLUDETAB Returns a list of all INCLUDES in a program
GUI_RUN Start a File or Program Asynchronously with ShellExecute
RPY_TRANSACTION_READ Given a transaction, return the program and screen or given a program and screen, return the transactions that use the program and screen.