So, I found out today that my Silver game has been erased due to a dead internal battery. Awesome. There goes all of my hard work over the course of 11 years.
Anyway, are there any glitches I can do in Silver without a Gameshark or memory editor? If I can't save my game, then I'll fork around with it instead.
Do you have a GBA SP? Start a new save and leave the game running and charged in for 100 hours on the RTC, and that should fully recharge the battery without you having to replace it manually.
If you don't have a GBA SP, you can replace the battery manually. See here for more details.
Most of the glitches in Generation II aren't really worth it or are impossible without a save. A few include the Sketch glitch (requiring a suitable Trainer house trainer), the bad clone glitch, Day-Light Saving Time exploit (get calls one after the other), the Japanese only Bug Catching Contest glitch and the Trainer House glitch with its derivatives (requiring a bad clone for the known replicable method).
There are other useful glitches between two games, like the Johto guard glitch (requiring a ????? FF), trade evolution glitch (get glitch moves on to Gen I) and shiny Ditto glitch (basically transfer red Gyarados over to Gen I, find a Ditto mimic its transform and transform into the transformation and capture it).
Some more include Coin Case glitches and the sort of 'time travel glitches' you'd expect of Generation IV, like waiting in front of the Elite Four for your rival to pop up and then him walking through you IIRC.
Also, trade a Pokémon with move hex:00 from Red/Blue to Gold/Silver for an equivalent move which activates a glitch dimension. In Crystal, there is also corrupting the map by viewing a ????? (00)'s stats ('missingning').
More: the Present glitch, Egg black out glitch (trade to only have an Eggs left in the party). The experience underflow glitch persists, though you'll have to trade a level 1 Pokémon from Generation I. Love Ball oversight: it has 8x on the same gender rather than the opposite.
Light Ball/Thick Club 1024 Attack/Sp. Attack overflow (with stat boosts), not possible in Stadium 2, but it is possible with reflect and light screen to overflow 999 defense to 1024 and come back past 0 in Generation I, but I'm not sure about Generation II.