--- a/gamelib/products.py	Sun May 06 17:12:40 2012 +0200
+++ b/gamelib/products.py	Sun May 06 17:39:37 2012 +0200
@@ -6,27 +6,50 @@
     PREREQUISITES = ()
     ACQUISITION_CHANCE = 0.8
     COST = 0
+    UPGRADE_REQUIREMENT = 1
+    STARTING_PRODUCT = False
 
-    def __init__(self):
-        self.points = 0
+    def __init__(self, points=0):
+        self.points = points
 
-    def spend_points(self, points):
-        self.points += points
+    def spend_point(self):
+        self.points += 1
+
+    def can_spend(self, lab):
+        extra = self.UPGRADE_REQUIREMENT * self.points + 1
+        return lab.meet_requirements(self, extra)
 
 
 class MachineGun(Product):
     NAME = "Machine gun"
     COST = 100
+    STARTING_PRODUCT = True
+
+    def __init__(self):
+        self.points = 1
+
+    def spend_point(self):
+        raise NotImplementedError()
+
+    def can_spend(self, lab):
+        return False
 
 
-class TeslaGun(Product):
-    NAME = "Tesla gun"
+class LightningGun(Product):
+    NAME = "Lightning gun"
     PREREQUISITES = (
         (research.Tesla, 1),
         )
     COST = 300
 
 
+class TeslaTank(Product):
+    NAME = "Tesla tank"
+    PREREQUISITES = (
+        (research.Tesla, 3),
+        )
+
+
 class DoomsdayVirus(Product):
     NAME = "Doomsday virus"
     PREREQUISITES = (