Here's a screenshot of my fairly basic conky. I compiled manually because by default you can't display the battery power.

Code:
# Colors for dark background

# Set to yes if you want Conky to be forked in the background
background yes


# Use Xft?
use_xft yes


# Xft font when Xft is enabled
#xftfont Trebuchet MS:size=10


# Text alpha when using Xft
xftalpha 0.9


# Update interval in seconds
update_interval 1.0
update_interval_on_battery 5.0


# This is the number of times Conky will update before quitting.
# Set to zero to run forever.
total_run_times 0


# Create own window instead of using desktop (required in nautilus)
own_window yes


# If own_window is yes, you may use type normal, desktop or override
# Panel mode seems to keep it from closing when show desktop is clicked
own_window_type normal


# Use pseudo transparency with own_window?
own_window_transparent yes


# If own_window is yes, these window manager hints may be used
own_window_hints undecorated,below,sticky,skip_taskbar,skip_pager


# Window color
# own_window_colour gray


# Use conky's argb transparency
own_window_argb_visual yes
own_window_argb_value 90


# Use double buffering (reduces flicker, may not work for everyone)
double_buffer yes


# Minimum size of text area
#minimum_size 210 480
minimum_size 210 220


# Maximum width
maximum_width 220


# Draw shades?
draw_shades no


# Draw outlines?
draw_outline no


# Draw borders around text
draw_borders no


# Draw borders around graphs
draw_graph_borders yes


# Stippled borders?
# stippled_borders 8


# border margins
# border_margin 2


# border width
# border_width 1


# Default colors and also border colors
default_color EEEEEC #Default GNOME off-white
default_shade_color red
default_outline_color green


# Text alignment, other possible values are commented
#alignment top_left
alignment top_right
#alignment bottom_left
#alignment bottom_right
#alignment none


# Gap between borders of screen and text
# same thing as passing -x at command line
gap_x 8
gap_y 36


# Subtract file system buffers from used memory?
no_buffers yes


# set to yes if you want all text to be in uppercase
uppercase no


# number of cpu samples to average
cpu_avg_samples 1


# Force UTF8? note that UTF8 support required XFT
override_utf8_locale no


# -- Lua Load -- #
lua_load ~/Scripts/draw_bg.lua
lua_draw_hook_pre draw_bg


# variable is given either in format $variable or in ${variable}
# stuff after 'TEXT' will be formatted on screen


TEXT
#${font Ubuntu:style=Bold:size=35}${alignc}${time %l:%M %p}${font Trebuchet MS:size=20}
#${font Purisa:size=20}${alignc}${color2}${time %b %d, %Y}${font Trebuchet MS:size=10}
#
${font Cantarell Bold:size=7}
## System info
${goto 6}${font OpenLogos:size=36}u${font Cantarell Bold:size=10}${goto 52}${voffset -37}${goto 60}Ubuntu GNOME 13.04
${goto 52}${goto 60}$nodename
${goto 52}${goto 60}$kernel${font Cantarell Bold:size=7}


#Uptime
${goto 16}${font Cantarell Bold:size=9}uptime${font Cantarell Bold:size=10}${goto 65}${voffset -2}$uptime${font Cantarell Bold:size=7}


#CPU
${goto 16}${font Cantarell Bold:size=9}cpu${goto 65}${font Cantarell Bold:size=10}${voffset -2}${cpu cpu0}%${goto 105}${cpubar 10,100 cpu0}
#RAM
${goto 16}${font Cantarell Bold:size=9}ram${goto 65}${font Cantarell Bold:size=10}${voffset -2}${memperc}%${goto 105}${membar 10,100}${font Cantarell Bold:size=7}


#File system
#${goto 16}${font Cantarell Bold:size=9}home${goto 65}${font Cantarell Bold:size=10}${voffset -2}${fs_used_perc /home}%${goto 105}${fs_bar 10,100 /home}
#${goto 16}${font Cantarell Bold:size=9}root${goto 65}${font Cantarell Bold:size=10}${voffset -2}${fs_used_perc /}%${goto 105}${fs_bar 10,100 /}${font Cantarell Bold:size=7}
#
#Battery, cpu temp, fan speed
${goto 16}${font Cantarell Bold:size=9}temp${font Cantarell Bold:size=10}${goto 65}${voffset -2}${acpitemp} deg. C
${goto 16}${font Cantarell Bold:size=9}fan${font Cantarell Bold:size=10}${goto 65}${voffset -2}${ibm_fan} RPM${font Cantarell Bold:size=9}


${goto 16}${font Cantarell Bold:size=9}bat${font Cantarell Bold:size=10}${goto 65}${voffset -7}${battery_percent}%
${goto 65}${battery_rate} W
And the lua script:

Code:
--[[Background by londonali1010 (2009)


This script draws a background to the Conky window. It covers the whole of the Conky window, but you can specify rounded corners, if you wish.


To call this script in Conky, use (assuming you have saved this script to ~/scripts/):
	lua_load ~/.scripts/draw_bg.lua
	lua_draw_hook_pre draw_bg


Changelog:
+ v1.0 -- Original release (07.10.2009)
]]


-- Change these settings to affect your background.
-- "corner_r" is the radius, in pixels, of the rounded corners. If you don't want rounded corners, use 0.


corner_r=45


-- Set the colour and transparency (alpha) of your background.


bg_colour=0x000000
bg_alpha=0.9


require 'cairo'
function rgb_to_r_g_b(colour,alpha)
	return ((colour / 0x10000) % 0x100) / 255., ((colour / 0x100) % 0x100) / 255., (colour % 0x100) / 255., alpha
end


function conky_draw_bg()
	if conky_window==nil then return end
	local w=conky_window.width
	local h=conky_window.height
	local cs=cairo_xlib_surface_create(conky_window.display, conky_window.drawable, conky_window.visual, w, h)
	cr=cairo_create(cs)
	
	cairo_move_to(cr,corner_r,0)
	cairo_line_to(cr,w-corner_r,0)
	cairo_curve_to(cr,w,0,w,0,w,corner_r)
	cairo_line_to(cr,w,h-corner_r)
	cairo_curve_to(cr,w,h,w,h,w-corner_r,h)
	cairo_line_to(cr,corner_r,h)
	cairo_curve_to(cr,0,h,0,h,0,h-corner_r)
	cairo_line_to(cr,0,corner_r)
	cairo_curve_to(cr,0,0,0,0,corner_r,0)
	cairo_close_path(cr)
	
	cairo_set_source_rgba(cr,rgb_to_r_g_b(bg_colour,bg_alpha))
	cairo_fill(cr)
end